Pyroglutamic acid derivatives and related compounds which inhibit leukocyte adhesion mediated by VLA-4

ABSTRACT

Disclosed are pyroglutamic acid derivatives and related compounds which bind VLA-4. Certain of these compounds also inhibit leukocyte adhesion and, in particular, leukocyte adhesion mediated by VLA-4. Such compounds are useful in the treatment of inflammatory diseases in a mammalian patient, e.g., human, such as asthma, Alzheimer&#39;s disease, atherosclerosis, AIDS dementia, diabetes, inflammatory bowel disease, rheumatoid arthritis, tissue transplantation, tumor metastasis and myocardial ischemia. The compounds can also be administered for the treatment of inflammatory brain diseases such as multiple sclerosis.

This application claims the benefit of U.S. Provisional Application No.60/198,244, filed Jan. 26, 1999, which was converted under 37 C.F.R.§1.53(c)(2)(i) from U.S. patent application Ser. No. 09/238,661.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to compounds which inhibit leukocyte adhesionand, in particular, leukocyte adhesion mediated by VLA-4.

References

The following publications, patents and patent applications are cited inthis application as superscript numbers:

1 Hemler and Takada, European Patent Application Publication No.330,506, published Aug. 30, 1989

2 Elices, et al., Cell, 60:577-584 (1990)

3 Springer, Nature, 346:425-434 (1990)

4 Osborn, Cell, 62:3-6 (1990)

5 Vedder, et al., Surgery, 106:509 (1989)

6 Pretolani, et al., J. Exp. Med., 180:795 (1994)

7 Abraham, et al., J. Clin. Invest., 93:776 (1994)

8 Mulligan, et al., J. Immunology, 150:2407 (1993)

9 Cybulsky, et al., Science, 251:788 (1991)

10 Li, et al., Arterioscler. Thromb., 13:197 (1993)

11 Sasseville, et al., Am. J. Path., 144:27 (1994)

12 Yang, et al., Proc. Nat. Acad. Science (USA), 90 10494 (1993)

13 Burkly, et al., Diabetes, 43:529 (1994)

14 Baron, et al., J. Clin. Invest., 93:1700 (1994)

15 Hamann, et al., J. Immunology, 152:3238 (1994)

16 Yednock, et al., Nature, 356:63 (1992)

17 Baron, et al., J. Exp. Med., 177:57 (1993)

18 van Dinther-Janssen, et al., J. Immunology, 147:4207 (1991)

19 van Dinther-Janssen, et al., Annals. Rheumatic Dis., 52:672 (1993)

20 Elices, et al., J. Clin. Invest., 93:405 (1994)

21 Postigo, et al., J. Clin. Invest., 89:1445 (1991)

22 Paul, et al., Transpl. Proceed., 25:813 (1993)

23 Okarhara, et al., Can. Res., 54:3233 (1994)

24 Paavonen, et al., Int. J. Can., 58:298 (1994)

25 Schadendorf, et al., J. Path., 170:429 (1993)

26 Bao, et al., Diff., 52:239 (1993)

27 Lauri, et al., British J. Cancer, 68:862 (1993)

28 Kawaguchi, et al., Japanese J. Cancer Res., 83:1304 (1992)

29 Kogan, et al., U.S. Pat. No. 5,510,332, issued Apr. 23, 1996

30 International Patent Appl. Publication No. WO 96/01644

All of the above publications, patents and patent applications areherein incorporated by reference in their entirety to the same extent asif each individual publication, patent or patent application wasspecifically and individually indicated to be incorporated by referencein its entirety.

2. State of the Art

VLA-4 (also referred to as α₄β₁ integrin and CD49d/CD29), firstidentified by Hemler and Takada¹ is a member of the β1 integrin familyof cell surface receptors, each of which comprises two subunits, an αchain and a β chain. VLA-4 contains an α4 chain and a β1 chain. Thereare at least nine β1 integrins, all sharing the same β1 chain and eachhaving a distinct α chain. These nine receptors all bind a differentcomplement of the various cell matrix molecules, such as fibronectin,laminin, and collagen. VLA-4, for example, binds to fibronectin. VLA-4also binds non-matrix molecules that are expressed by endothelial andother cells. These non-matrix molecules include VCAM-1, which isexpressed on cytokine-activated human umbilical vein endothelial cellsin culture. Distinct epitopes of VLA-4 are responsible for thefibronectin and VCAM-1 binding activities and each activity has beenshown to be inhibited independently².

Intercellular adhesion mediated by VLA-4 and other cell surfacereceptors is associated with a number of inflammatory responses. At thesite of an injury or other inflammatory stimulus, activated vascularendothelial cells express molecules that are adhesive for leukocytes.The mechanics of leukocyte adhesion to endothelial cells involves, inpart, the recognition and binding of cell surface receptors onleukocytes to the corresponding cell surface molecules on endothelialcells. Once bound, the leukocytes migrate across the blood vessel wallto enter the injured site and release chemical mediators to combatinfection. For reviews of adhesion receptors of the immune system, see,for example, Springer³ and Osborn⁴.

Inflammatory brain disorders, such as experimental autoimmuneencephalomyelitis (EAE), multiple sclerosis (MS) and meningitis, areexamples of central nervous system disorders in which theendothelium/leukocyte adhesion mechanism results in destruction tootherwise healthy brain tissue. Large numbers of leukocytes migrateacross the blood brain barrier (BBB) in subjects with these inflammatorydiseases. The leukocytes release toxic mediators that cause extensivetissue damage resulting in impaired nerve conduction and paralysis.

In other organ systems, tissue damage also occurs via an adhesionmechanism resulting in migration or activation of leukocytes. Forexample, it has been shown that the initial insult following myocardialischemia to heart tissue can be further complicated by leukocyte entryto the injured tissue causing still further insult (Vedder et al.⁵).Other inflammatory conditions mediated by an adhesion mechanism include,by way of example, asthma⁶⁻⁸, Alzheimer's disease, atherosclerosis⁹⁻¹⁰,AIDS dementia¹¹, diabetes¹²⁻¹⁴ (including acute juvenile onsetdiabetes), inflammatory bowel disease¹⁵ (including ulcerative colitisand Crohn's disease), multiple sclerosis¹⁶⁻¹⁷, rheumatoidarthritis¹⁸⁻²¹, tissue transplantation²², tumor metastasis²³⁻²⁸,meningitis, encephalitis, stroke, and other cerebral traumas, nephritis,retinitis, atopic dermatitis, psoriasis, myocardial ischemia and acuteleukocyte-mediated lung injury such as that which occurs in adultrespiratory distress syndrome.

In view of the above, assays for determining the VLA-4 level in abiological sample containing VLA-4 would be useful, for example, todiagnosis VLA-4 mediated conditions. Additionally, despite theseadvances in the understanding of leukocyte adhesion, the art has onlyrecently addressed the use of inhibitors of adhesion in the treatment ofinflammatory brain diseases and other inflammatory conditions^(29,30).The present invention addresses these and other needs.

SUMMARY OF THE INVENTION

This invention provides compounds which bind to VLA-4. Such compoundscan be used, for example, to assay for the presence of VLA-4 in a sampleand in pharmaceutical compositions to inhibit cellular adhesion mediatedby VLA-4, for example, binding of VCAM-1 to VLA-4. The compounds of thisinvention have a binding affinity to VLA-4 as expressed by an IC₅₀ ofabout 15 μM or less (as measured using the procedures described inExample A below) which compounds are defined by formula I below:

wherein

R¹ is selected from the group consisting of alkyl, substituted alkyl,aryl, substituted aryl, cycloalkyl, substituted cycloalkyl,heterocyclic, substituted heterocylic, heteroaryl, substitutedheteroaryl and —C(O)OR¹;

R² is selected from the group consisting of alkylene having from 2 to 4carbon atoms in the alkylene chain, substituted alkylene having from 2to 4 carbon atoms in the alkylene chain, heteroalkylene containing from1 to 3 carbon atoms and from 1 to 2 heteroatoms selected from nitrogen,oxygen and sulfur and having from 2 to 4 atoms in the heteroalkylenechain, and substituted heteroalkylene containing, in the heteroalkylenechain, from 1 to 3 carbon atoms and from 1 to 2 heteroatoms selectedfrom nitrogen, oxygen and sulfur and having from 2 to 4 atoms in theheteroalkylene chain;

R³ is selected from the group consisting of hydrogen, alkyl, substitutedalkyl, cycloalkyl, substituted cycloalkyl, cycloalkenyl, substitutedcycloalkenyl, aryl, substituted aryl, heteroaryl, substitutedheteroaryl, heterocyclic, substituted heterocyclic; or R³ can be joinedto R² to form a fused cycloalkyl, substititued cycloalkyl, cycloalkenyl,substituted cycloalkenyl, heterocyclic or substituted heterocyclic ring;

R⁴ is selected from the group consisting of isopropyl, —CH₂—X and ═CH—X,where X is selected from the group consisting of hydrogen, alkyl,substituted alkyl, cycloalkyl, substituted cycloalkyl, alkoxy,substituted alkoxy, aryl, substituted aryl, aryloxy, substitutedaryloxy, aryloxyaryl, substituted aryloxyaryl, heteroaryl, substitutedheteroaryl, heterocyclic, substituted heterocyclic, acylamino, carboxyl,carboxylalkyl, carboxyl-substituted alkyl, carboxyl-cycloalkyl,carboxyl-substituted cycloalkyl, carboxylaryl, carboxyl-substitutedaryl, carboxylheteroaryl, carboxyl-substituted heteroaryl,carboxyheterocyclic, carboxy-substituted heterocyclic, and hydroxyl withthe proviso that when R⁴ is ═CH—X then (H) is removed from the formulaand X is not hydroxyl;

W is oxygen or sulfur;

and pharmaceutically acceptable salts thereof.

In another embodiment, the compounds of this invention can also beprovided as prodrugs which convert (e.g., hydrolyze, metabolize, etc.)in vivo to a compound of formula I above. In a preferred example of suchan embodiment, the carboxylic acid in the compound of formula I ismodified into a group which, in vivo, will convert to the carboxylicacid (including salts thereof). In a particularly preferred embodiment,such prodrugs are represented by compounds of formula IA:

wherein

R¹ is selected from the group consisting of alkyl, substituted alkyl,aryl, substituted aryl, cycloalkyl, substituted cycloalkyl,heterocyclic, substituted heterocylic, heteroaryl, substitutedheteroaryl and —C(O)OR¹;

R² is selected from the group consisting of alkylene having from 2 to 4carbon atoms in the alkylene chain, substituted alkylene having from 2to 4 carbon atoms in the alkylene chain, heteroalkylene containing from1 to 3 carbon atoms and from 1 to 2 heteroatoms selected from nitrogen,oxygen and sulfur and having from 2 to 4 atoms in the heteroalkylenechain, and substituted heteroalkylene containing, in the heteroalkylenechain, from 1 to 3 carbon atoms and from 1 to 2 heteroatoms selectedfrom nitrogen, oxygen and sulfur and having from 2 to 4 atoms in theheteroalkylene chain;

R³ is selected from the group consisting of hydrogen, alkyl, substitutedalkyl, cycloalkyl, substituted cycloalkyl, cycloalkenyl, substitutedcycloalkenyl, aryl, substituted aryl, heteroaryl, substitutedheteroaryl, heterocyclic, substituted heterocyclic; or R³ can be joinedto R² to form a fused cycloalkyl, substititued cycloalkyl, cycloalkenyl,substituted cycloalkenyl, heterocyclic or substituted heterocyclic ring;

R⁴ is selected from the group consisting of isopropyl, —CH₂—X and ═CH—X,where X is selected from the group consisting of hydrogen, alkyl,substituted alkyl, cycloalkyl, substituted cycloalkyl, alkoxy,substituted alkoxy, aryl, substituted aryl, aryloxy, substitutedaryloxy, aryloxyaryl, substituted aryloxyaryl, heteroaryl, substitutedheteroaryl, heterocyclic, substituted heterocyclic, acylamino, carboxyl,carboxylalkyl, carboxyl-substituted alkyl, carboxyl-cycloalkyl,carboxyl-substituted cycloalkyl, carboxylaryl, carboxyl-substitutedaryl, carboxylheteroaryl, carboxyl-substituted heteroaryl,carboxyheterocyclic, carboxy-substituted heterocyclic, and hydroxyl withthe proviso that when R⁴ is ═CH—X then (H) is removed from the formulaand X is not hydroxyl;

R⁵ is selected from the group consisting of amino, alkoxy, substitutedalkoxy, cycloalkoxy, substituted cycloalkoxy, aryloxy, substitutedaryloxy, heteroaryloxy, substituted heteroaryloxy, heterocyclyloxy,substituted heterocyclyloxy, —NHOY where Y is hydrogen, alkyl,substituted alkyl, aryl, or substituted aryl, and —NH(CH₂)_(p)COOY′where Y′ is hydrogen, alkyl, substituted alkyl, aryl, or substitutedaryl, and p is an integer of from 1 to 8;

W is oxygen or sulfur;

and pharmaceutically acceptable salts thereof;

with the provisos that:

(a) when R¹ is benzyl, R² is —CH₂CH₂—, R³ is hydrogen, R⁴ is benzyl,then R⁵ is not ethyl;

(b) when R¹ is 3,4-dichlorobenzyl, R² is —CH₂CH₂—, R³ is hydrogen, R⁴ is4-(phenylcarbonylamino)benzyl, then R⁵ is not methyl;

(c) when R¹ is benzyl, R² is —CH₂CH₂—, R³ is hydrogen, R⁴ is4-hydroxybenzyl, then R⁵ is not isopropyl or tert-butyl;

(d) when R¹ is 4-flurobenzyl, R² is —CH₂CH₂—, R³ is hydrogen, R⁵ istert-butyl, then R⁴ is not 4-hydroxybenzyl or4-(4-nitrophenoxycarbonyloxy)benzyl;

(e) when R¹ is 4-cyanobenzyl, R² is —CH₂CH₂—, R³ is hydrogen, R⁴ is4-hydroxybenzyl, then R⁵ is not tert-butyl; and

(f) when R¹ is benzyloxycarbonyl, R² is —NHCH₂—, R³ is hydrogen, R⁵ istert-butyl, then R⁴ is not 4-hydroxybenzyl or4-(N,N-dimethylcarbamyloxy)benzyl.

In a preferred embodiment, R¹ is a group having the formula:

wherein

R⁶ and R⁷ are independently selected from the group consisting ofhydrogen, alkyl, alkoxy, amino, cyano, halo and nitro; and

Z is CH or N.

Preferably, Z is CH.

Preferably, one of R⁶ and R⁷ is hydrogen and the other is selected fromthe group consisting of hydrogen, methyl, methoxy, amino, chloro,fluoro, cyano or nitro; or both R⁶ and R⁷ are chloro.

In a particularly preferred embodiment, R¹ is selected from the groupconsisting of benzyl, 4-aminobenzyl, 3-chlorobenzyl, 4-chlorobenzyl,3,4-dichlorobenzyl, 4-cyanobenzyl, 4-fluorobenzyl, 4-methylbenzyl,4-methoxybenzyl, 4-nitrobenzyl, benzyloxycarbonyl, (pyrdin-3-yl)methyland the like.

Preferably, R² is selected from the group consisting of alkylene having2 or 3 carbon atoms in the alkylene chain, substituted alkylene having 2or 3 carbon atoms in the alkylene chain, heteroalkylene containing 1 or2 carbon atoms and 1 heteroatom selected from nitrogen, oxygen andsulfur and having 2 or 3 atoms in the heteroalkylene chain, andsubstituted heteroalkylene containing, in the heteroalkylene chain, 1 or2 carbon atoms and 1 heteroatom selected from nitrogen, oxygen andsulfur and having 2 or 3 atoms in the heteroalkylene chain.

In a particularly preferred embodiment, R² is selected from the groupconsisting of —CH₂CH₂—, —CH₂—S—CH₂—, —CH₂—O—CH₂— and —NHCH₂—.Accordingly, R² when joined with the other atoms of thenitrogen-containing ring structure preferably forms a 2-pyrrolidinone,3-oxothiomorpholine, 3-oxomorpholine or 2-imidazolidinone ring. Inanother preferred embodiment, R³ is joined to R² to form a5-oxo-4-azatricyclo[4.2.1.0(3,7)]nonane ring.

Preferably, in the compounds of formula I and IA above, R³ is hydrogenor it is joined with R² to form a5-oxo-4-azatricyclo[4.2.1.0(3,7)]nonane ring. More preferably, R³ ishydrogen.

R⁴ is preferably selected from all possible isomers arising bysubstitution with the following groups:

4-methylbenzyl,

4-hydroxybenzyl,

4-methoxybenzyl,

4-t-butoxybenzyl,

4-benzyloxybenzyl,

4-[φ—CH(CH₃)O—]benzyl,

4-[φ—CH(COOH)O—]benzyl,

4-[BocNHCH₂C(O)NH—]benzyl,

4-chlorobenzyl,

4-[NH₂CH₂C(O)NH—]benzyl,

4-carboxybenzyl,

4-[CbzNHCH₂CH₂NH—]benzyl,

3-hydroxy-4-(φ—OC(O)NH—)benzyl,

4-[HOOCCH₂CH₂C(O)NH—]benzyl,

benzyl,

4-[2′-carboxylphenoxy-]benzyl,

4-[φ—C(O)NH—]benzyl,

3-carboxybenzyl,

4-iodobenzyl,

4-hydroxy-3,5-diiodobenzyl,

4-hydroxy-3-iodobenzyl,

4-[2′-carboxyphenyl-]benzyl,

φ—CH₂CH₂—,

4-nitrobenzyl,

2-carboxybenzyl,

4-[dibenzylamino]-benzyl,

4-[(1′-cyclopropylpiperidin-4′-yl)C(O)NH—]benzyl,

4-[—NHC(O)CH₂NHBoc]benzyl,

4-carboxybenzyl,

4-hydroxy-3-nitrobenzyl,

4-[—NHC(O)CH(CH₃)NHBoc]benzyl,

4-[—NHC(O)CH(CH₂φ)NHBoc]benzyl,

isobutyl,

methyl,

4-[CH₃C(O)NH—]benzyl,

—CH₂-(3-indolyl),

n-butyl,

t-butyl-OC(O)CH₂—,

t-butyl-OC(O)CH₂CH₂—,

H₂NC(O)CH₂—,

H₂NC(O)CH₂CH₂—,

BocNH—(CH₂)₄—,

t-butyl-OC(O)—(CH₂)₂—,

HOOCCH₂—,

HOOC(CH₂)₂—,

H₂N(CH₂)₄—,

isopropyl,

(1-naphthyl)-CH₂—,

(2-naphthyl)-CH₂—,

(2-thiophenyl)-CH₂—,

(φ—CH₂—OC(O)NH—(CH₂)₄—,

cyclohexyl-CH₂—,

benzyloxy-CH₂—,

HOCH₂—,

5-(3-N-benzyl)imidazolyl-CH₂—,

2-pyridyl-CH₂—,

3-pyridyl-CH₂—,

4-pyridyl-CH₂—,

5-(3-N-methyl)imidazolyl-CH₂—,

N-benzylpiperid-4-yl-CH₂—,

N-Boc-piperidin-4-yl-CH₂—,

N-(phenyl-carbonyl)piperidin-4-yl-CH₂—,

H₃CSCH₂CH₂—,

1-N-benzylimidazol-4-yl-CH₂—,

iso-propyl-C(O)NH—(CH₂)₄—,

iso-butyl-C(O)NH—(CH₂)₄—,

phenyl-C(O)NH—(CH₂)₄—,

benzyl-C(O)NH—(CH₂)₄—,

allyl-C(O)NH—(CH₂)₄—,

4-(3-N-methylimidazolyl)-CH₂—,

4-imidazolyl,

4-[(CH₃)₂NCH₂CH₂CH₂—O—]benzyl,

4-[(benzyl)₂N—]-benzyl,

4-aminobenzyl,

allyloxy-C(O)NH(CH₂)₄—,

allyloxy-C(O)NH(CH₂)₃—,

allyloxy-C(O)NH(CH₂)₂—,

NH₂C(O)CH₂—,

φ—CH═,

2-pyridyl-C(O)NH—(CH₂)₄—,

4-methylpyrid-3-yl-C(O)NH—(CH₂)₄—,

3-methylthien-2-yl-C(O)NH—(CH₂)₄—,

2-pyrrolyl-C(O)NH—(CH₂)₄—,

2-furanyl-C(O)NH—(CH₂)₄—,

4-methylphenyl-SO₂—N(CH₃)CH₂C(O)NH(CH₂)₄—,

4-[cyclopentylacetylenyl]-benzyl,

4-[—NHC(O)-(N-Boc)-pyrrolidin-2-yl)]-benzyl-,

1-N-methylimidazol-4-yl-CH₂—,

1-N-methylimidazol-5-yl-CH₂—,

imidazol-5-yl-CH₂—,

6-methylpyrid-3-yl-C(O)NH—(CH₂)₄—,

4-[2′-carboxymethylphenyl]-benzyl,

4-[—NHC(O)NHCH₂CH₂CH₂—φ]-benzyl,

4-[—NHC(O)NHCH₂CH₂—φ]-benzyl,

—CH₂C(O)NH(CH₂)₄φ,

4-[φ(CH₂)₄O—]-benzyl,

4-[—C≡C—φ-4′φ]-benzyl,

4-[—C≡C—CH₂—O—S(O)₂-4′-CH₃—φ]-benzyl,

4-[—C≡C—CH₂NHC(O)NH₂]-benzyl,

4-[—C≡C—CH₂—O-4′-COOCH₂CH₃—φ]-benzyl,

4-[—C≡C—CH(NH₂)-cyclohexyl]-benzyl,

—(CH₂)₄NHC(O)CH₂-3-indolyl,

—(CH₂)₄NHC(O)CH₂CH₂-3-indolyl,

—(CH₂)₄NHC(O)-3-(5-methoxyindolyl),

—(CH₂)₄NHC(O)-3-(1-methylindolyl),

—(CH₂)₄NHC(O)-4-(—SO₂(CH₃)—φ),

—(CH₂)₄NHC(O)-4-(C(O)CH₃)-phenyl,

—(CH₂)₄NHC(O)-4-fluorophenyl,

—(CH₂)₄NHC(O)CH₂O-4-fluorophenyl,

4-[—C≡C-(2-pyridyl)]benzyl,

4-[—C≡C—CH₂—O-phenyl]benzyl,

4-[—C≡C—CH₂OCH₃]benzyl,

4-[—C≡C-(3-hydroxyphenyl)]benzyl,

4-[—C≡C—CH₂—O-4′-(—C(O)OC₂H₅)phenyl]benzyl,

4-[—C≡C—CH₂CH(C(O)OCH₃)₂]benzyl,

4-[—C≡C—CH₂NH-(4,5-dihydro-4-oxo-5-phenyl-oxazol-2-yl),

3-aminobenzyl,

4-[—C≡C—CH₂CH(NHC(O)CH₃)C(O)OH]-benzyl,

—CH₂C(O)NHCH(CH₃)φ,

—CH₂C(O)NHCH₂-(4-dimethylamino)-φ,

—CH₂C(O)NHCH₂-4-nitrophenyl,

—CH₂CH₂C(O)N(CH₃)CH₂—φ,

—CH₂CH₂C(O)NHCH₂CH₂-(N-methyl)-2-pyrrolyl,

—CH₂CH₂C(O)NHCH₂CH₂CH₂CH₃,

—CH₂CH₂C(O)NHCH₂CH₂-3-indolyl,

—CH₂C(O)N(CH₃)CH₂phenyl,

—CH₂C(O)NH(CH₂)₂-(N-methyl)-2-pyrrolyl,

—CH₂C(O)NHCH₂CH₂CH₂CH₃,

—CH₂C(O)NHCH₂CH₂-3-indolyl,

—(CH₂)₂C(O)NHCH(CH₃)φ,

—(CH₂)₂C(O)NHCH₂-4-dimethylaminophenyl,

—(CH₂)₂C(O)NHCH₂-4-nitrophenyl,

—CH₂C(O)NH-4-[—NHC(O)CH₃-phenyl],

—CH₂C(O)NH-4-pyridyl,

—CH₂C(O)NH-4-[dimethylaminophenyl],

—CH₂C(O)NH-3-methoxyphenyl,

—CH₂CH₂C(O)NH-4-chlorophenyl,

—CH₂CH₂C(O)NH-2-pyridyl,

—CH₂CH₂C(O)NH-4-methoxyphenyl,

—CH₂CH₂C(O)NH-3-pyridyl,

4-[(CH₃)₂NCH₂CH₂O—]benzyl,

—(CH₂)₃NHC(NH)NH—SO₂-4-methylphenyl,

4-[(CH₃)₂NCH₂CH₂O—]benzyl,

—(CH₂)₄NHC(O)NHCH₂CH₃,

—(CH₂)₄NHC(O)NH-phenyl,

—(CH₂)₄NHC(O)NH-4-methoxyphenyl,

4-[4′-pyridyl-C(O)NH—]benzyl,

4-[3′-pyridyl-C(O)NH—]benzyl,

4-[—NHC(O)NH-3′-methylphenyl]benzyl,

4-[—NHC(O)CH₂NHC(O)NH-3′-methylphenyl]benzyl,

4-[—NHC(O)-(2′,3′-dihydroindol-2-yl)]benzyl,

4-[—NHC(O)-(2′,3′-dihydro-N-Boc-indol-2-yl)]benzyl,

p-[—OCH₂CH₂-1′-(4′-pyrimidinyl)-piperazinyl]benzyl,

4-[—OCH₂CH₂-(1′-piperidinyl)benzyl,

4-[—OCH₂CH₂-(1′-pyrrolidinyl)]benzyl,

4-[—OCH₂CH₂CH₂-(1′-piperidinyl)]benzyl-,

—CH₂-3-(1,2,4-triazolyl),

4-[—OCH₂CH₂CH₂-4-(3′-chlorophenyl)-piperazin-1-yl]benzyl,

4-[—OCH₂CH₂N(φ)CH₂CH₃]benzyl,

4-[—OCH₂-3′-(N-Boc)-piperidinyl]benzyl,

4-[di-n-pentylamino]benzyl,

4-[n-pentylamino]benzyl,

4-[di-iso-propylamino-CH₂CH₂O—]benzyl,

4-[—OCH₂CH₂-(N-morpholinyl)]benzyl,

4-[—O-(3′-(N-Boc)-piperidinyl]benzyl,

4-[—OCH₂CH(NHBoc)CH₂cyclohexyl]benzyl,

p-[OCH₂CH₂-(N-piperidinyl]benzyl,

4-[—OCH₂CH₂CH₂-(4-m-chlorophenyl)-piperazin-1-yl]benzyl,

4-[—OCH₂CH₂-(N-homopiperidinyl)benzyl,

4-[—NHC(O)-3′-(N-Boc)-piperidinyl]benzyl,

4-[—OCH₂CH₂N(benzyl)₂]benzyl,

—CH₂-2-thiazolyl,

3-hydroxybenzyl,

4-[—OCH₂CH₂CH₂N(CH₃)₂]benzyl,

4-[—NHC(S)NHCH₂CH₂-(N-morpholino)]benzyl,

4-[—OCH₂CH₂N(C₂H₅)₂]benzyl,

4-[—OCH₂CH₂CH₂N(C₂H₅)₂]benzyl,

4-[CH₃(CH₂)₄NH—]benzyl,

4-[N-n-butyl,N-n-pentylamino-]benzyl,

4-[—NHC(O)-4′-piperidinyl]benzyl,

4-[—NHC(O)CH(NHBoc)(CH₂)₄NHCbz]benzyl,

4-[—NHC(O)-(1′,2′,3′,4′-tetrahydro-N-Boc-isoquinolin-1′-yl]benzyl,

p-[—OCH₂CH₂CH₂-1′-(4′-methyl)-piperazinyl]benzyl,

—(CH₂)₄NH-Boc,

3-[—OCH₂CH₂CH₂N(CH₃)₂]benzyl,

4-[—OCH₂CH₂CH₂N(CH₃)₂]benzyl,

3-[—OCH₂CH₂-(1′-pyrrolidinyl)]benzyl,

4-[—OCH₂CH₂CH₂N(CH₃)benzyl]benzyl,

4-[—NHC(S)NHCH₂CH₂CH₂-(N-morpholino)]benzyl,

4-[—OCH₂CH₂-(N-morpholino)]benzyl,

4-[—NHCH₂-(4′-chlorophenyl)]benzyl,

4-[—NHC(O)NH-(4′-cyanophenyl)]benzyl,

4-[—OCH₂COOH]benzyl,

4-[—OCH₂COO-t-butyl]benzyl,

4-[—NHC(O)-5′-fluoroindol-2-yl]benzyl,

4-[—NHC(S)NH(CH₂)₂-1-piperidinyl]benzyl,

4-[—N(SO₂CH₃)(CH₂)₃—N(CH₃)₂]benzyl,

4-[—NHC(O)CH₂CH(C(O)OCH₂φ)—NHCbz]benzyl,

4-[—NHS(O)₂CF₃]benzyl,

3-[—O-(N-methylpiperidin-4′-yl]benzyl,

4-[—C(═NH)NH₂]benzyl,

4-[—NHSO₂—CH₂Cl]benzyl,

4-[—NHC(O)-(1′,2′,3′,4′-tetrahydroisoquinolin-2′-yl]benzyl,

4-[—NHC(S)NH(CH₂)₃-N-morpholino]benzyl,

4-[—NHC(O)CH(CH₂CH₂CH₂CH₂NH₂)NHBoc]benzyl,

4-[—C(O)NH₂]benzyl,

4-[—NHC(O)NH-3′-methoxyphenyl]benzyl,

4-[—OCH₂CH₂-indol-3′-yl]benzyl,

4-[—OCH₂C(O)NH-benzyl]benzyl,

4-[—OCH₂C(O)O-benzyl]benzyl,

4-[—OCH₂C(O)OH]benzyl,

4-[—OCH₂-2′-(4′,5′-dihydro)imidazolyl]benzyl,

—CH₂C(O)NHCH₂-(4-dimethylamino)phenyl,

—CH₂C(O)NHCH₂-(4-dimethylamino)phenyl,

4-[—NHC(O)-L-2′-pyrrolidinyl-N—SO₂-4′-methylphenyl]benzyl,

4-[—NHC(O)NHCH₂CH₂CH₃]benzyl,

4-aminobenzyl]benzyl,

4-[—OCH₂CH₂-1-(4-hydroxy-4-(3-methoxypyrrol-2-yl)-piperazinyl]benzyl,

4-[—O-(N-methylpiperidin-4′-yl)]benzyl,

3-methoxybenzyl,

4-[—NHC(O)-piperidin-3′-yl]benzyl,

4-[—NHC(O)-pyridin-2′-yl]benzyl,

4-[—NHCH₂-(4′-chlorophenyl)]benzyl,

4-[—NHC(O)—(N-(4′—CH₃—φ—SO₂)-L-pyrrolidin-2′-yl)]benzyl,

4-[—NHC(O)NHCH₂CH₂—φ]benzyl,

4-[—OCH₂C(O)NH₂]benzyl,

4-[—OCH₂C(O)NH-t-butyl]benzyl,

4-[—OCH₂CH₂-1-(4-hydroxy-4-phenyl)-piperidinyl]benzyl,

4-[—NHSO₂—CH═CH₂]benzyl,

4-[—NHSO₂—CH₂CH₂Cl]benzyl,

—CH₂C(O)NHCH₂CH₂N(CH₃)₂,

4-[(1′-Cbz-piperidin-4′-yl)C(O)NH—]benzyl,

4-[(1′-Boc-piperidin-4′-yl)C(O)NH—]benzyl,

4-[(2′-bromophenyl)C(O)NH—]benzyl,

4-[—NHC(O)-pyridin-4′-yl]benzyl,

4-[(4′-(CH₃)₂NC(O)O—)phenyl)-C(O)NH—]benzyl,

4-[—NHC(O)-1′-methylpiperidin-4′-yl-]benzyl,

4-(dimethylamino)benzyl,

4-[—NHC(O)-(1′-N-Boc)-piperidin-2′-yl]benzyl,

3-[—NHC(O)-pyridin-4′-yl]benzyl,

4-[(tert-butyl-O(O)CCH₂—O-benzyl)-NH—]benzyl,

[BocNHCH₂C(O)NH—]butyl,

4-benzylbenzyl,

2-hydroxyethyl,

4-[(Et)₂NCH₂CH₂CH₂NHC(S)NH—]benzyl,

4-[(1′-Boc-4′-hydroxypyrrolidin-2′-yl)C(O)NH—]benzyl,

4-[φCH₂CH₂CH₂NHC(S)NH—]benzyl,

4-[(perhydroindolin-2′-yl)C(O)NH—]benzyl,

2-[4-hydroxy-4-(3-methoxythien-2-yl)piperidin-1-yl]ethyl,

4-[(1′-Boc-perhydroindolin-2′-yl)-C(O)NH—]benzyl,

4-[N-3-methylbutyl-N-trifluoromethanesulfonyl)amino]benzyl,

4-[N-vinylsulfonyl)amino]benzyl,

4-[2-(2-azabicyclo[3.2.2]octan-2-yl)ethyl-O—]benzyl,

4-[4′-hydroxypyrrolidin-2′-yl)C(O)NH—]benzyl,

4-(φNHC(S)NH)benzyl,

4-(EtNHC(S)NH)benzyl,

4-(φCH₂NHC(S)NH)benzyl,

3-[(1′-Boc-piperidin-2′-yl)C(O)NH—]benzyl,

3-[piperidin-2′-yl-C(O)NH—]benzyl,

4-[(3′-Boc-thiazolidin-4′-yl)C(O)NH—]benzyl,

4-(pyridin-3′-yl-NHC(S)NH)benzyl,

4-(CH₃—NHC(S)NH)benzyl,

4-(H₂NCH₂CH₂CH₂C(O)NH)benzyl,

4-(BocHNCH₂CH₂CH₂C(O)NH)benzyl,

4-(pyridin-4′-yl-CH₂NH)benzyl,

4-[(N,N-di(4-N,N-dimethylamino)benzyl)amino]benzyl,

4-[(1-Cbz-piperidin-4-yl)C(O)NH—]butyl,

4-[φCH₂OCH₂(BocHN)CHC(O)NH]benzyl,

4-[(piperidin-4′-yl)C(O)NH—]benzyl,

4-[(pyrrolidin-2′-yl)C(O)NH—]benzyl,

4-(pyridin-3′-yl-C(O)NH)butyl,

4-(pyridin-4′-yl-C(O)NH)butyl,

4-(pyridin-3′-yl-C(O)NH)benzyl,

4-[CH₃NHCH₂CH₂CH₂C(O)NH—]benzyl,

4-[CH₃N(Boc)CH₂CH₂CH₂C(O)NH—]benzyl,

4-(aminomethyl)benzyl,

4-[φCH₂OCH₂(H₂N)CHC(O)NH]benzyl,

4-[(1′,4′-di(Boc)piperazin-2′-yl)-C(O)NH—]benzyl,

4-[(piperazin-2′-yl)-C(O)NH—]benzyl,

4-[(N-toluenesulfonylpyrrolidin-2′-yl)C(O)NH—]butyl,

4-[—NHC(O)-4′-piperidinyl]butyl,

4-[—NHC(O)-1′-N-Boc-piperidin-2′-yl]benzyl,

4-[—NHC(O)-piperidin-2′-yl]benzyl,

4-[(1′-N-Boc-2′,3′-dihydroindolin-2′-yl)-C(O)NH]benzyl,

4-(pyridin-3′-yl-CH₂NH)benzyl,

4-[(piperidin-1′-yl)C(O)CH₂—O—]benzyl,

4-[(CH₃)₂CH)₂NC(O)CH₂—O—]benzyl,

4-[HO(O)C(Cbz-NH)CHCH₂CH₂—C(O)NH—]benzyl,

4-[φCH₂O(O)C(Cbz-NH)CHCH₂CH₂—C(O)NH—]benzyl,

4-[—NHC(O)-2′-methoxyphenyl]benzyl,

4-[(pyrazin-2′-yl)C(O)NH—]benzyl,

4-[HO(O)C(NH₂)CHCH₂CH₂—C(O)NH—]benzyl,

4-(2′-formyl-1′,2′,3′,4′-tetrahydroisoquinolin-3′-yl-CH₂NH—)benzyl,

N-Cbz-NHCH₂—,

4-[(4′-methylpiperazin-1′-yl)C(O)O—]benzyl,

4-[CH₃(N-Boc)NCH₂C(O)NH—]benzyl,

4-[—NHC(O)-(1′,2′,3′,4′-tetrahydro-N-Boc-isoquinolin-3′-yl]-benzyl,

4-[CH₃NHCH₂C(O)NH—]benzyl,

(CH₃)₂NC(O)CH₂—,

4-(N-methylacetamido)benzyl,

4-(1′,2′,3′,4′-tetrahydroisoquinolin-3′-yl-CH₂NH—)benzyl,

4-[(CH₃)₂NHCH₂C(O)NH—]benzyl,

(1-toluenesulfonylimidizol-4-yl)methyl,

4-[(1′-Boc-piperidin-4′-yl)C(O)NH—]benzyl,

4-trifluoromethylbenzyl,

4-[(2′-bromophenyl)C(O)NH—]benzyl,

4-[(CH₃)₂NC(O)NH—]benzyl,

4-[CH₃OC(O)NH—]benzyl,

4-[(CH₃)₂NC(O)O—]benzyl,

4-[(CH₃)₂NC(O)N(CH₃)—]benzyl,

4-[CH₃OC(O)N(CH₃)—]benzyl,

4-(N-methyltrifluoroacetamido)benzyl,

4-[(1′-methoxycarbonylpiperidin-4′-yl)C(O)NH—]benzyl,

4-[(4′-phenylpiperidin-4′-yl)C(O)NH—]benzyl,

4-[(4′-phenyl-1′-Boc-piperidin-4′-yl)-C(O)NH—]benzyl,

4-[(piperidin-4′-yl)C(O)O—]benzyl,4-[(1′-methylpiperidin-4′-yl)-O—]benzyl,

4-[(1′-methylpiperidin-4′-yl)C(O)O—]benzyl,

4-[(4′-methylpiperazin-1′-yl)C(O)NH—]benzyl,

3-[(CH₃)₂NC(O)O—]benzyl,

4-[(4′-phenyl-1′-Boc-piperidin-4′-yl)-C(O)O—]benzyl,

4-(N-toluenesulfonylamino)benzyl,

4-[(CH₃)₃CC(O)NH—]benzyl,

4-[(morpholin-4′-yl)C(O)NH—]benzyl,

4-[(CH₃CH₂)₂NC(O)NH—]benzyl,

4-[—C(O)NH-(4′-piperidinyl)]benzyl,

4-[(2′-trifluoromethylphenyl)C(O)NH—]benzyl,

4-[(2′-methylphenyl)C(O)NH—]benzyl,

4-[(CH₃)₂NS(O)₂O—]benzyl,

4-[(pyrrolidin-2′-yl)C(O)NH—]benzyl,

4-[—NHC(O)-piperidin-1′-yl]benzyl,

4-[(thiomorpholin-4′-yl)C(O)NH—]benzyl,

4-[(thiomorpholin-4′-yl sulfone)-C(O)NH—]benzyl,

4-[(morpholin-4′-yl)C(O)O—]benzyl,

3-nitro-4-(CH₃OC(O)CH₂O—)benzyl,

(2-benzoxazolinon-6-yl)methyl-,

(2H-1,4-benzoxazin-3(4H)-one-7-yl)methyl-,

4-[(CH₃)₂NS(O)₂NH—]benzyl,

4-[(CH₃)₂NS(O)₂N(CH₃)—]benzyl,

4-[(thiomorpholin-4′-yl)C(O)O—]benzyl,

4-[(thiomorpholin-4′-yl sulfone)-C(O)O—]benzyl,

4-[(piperidin-1′-yl)C(O)O—]benzyl,

4-[(pyrrolidin-1′-yl)C(O)O—]benzyl,

4-[(4′-methylpiperazin-1′-yl)C(O)O—]benzyl,

4-[(2′-methylpyrrolidin-1′-yl)-,

(pyridin-4-yl)methyl-,

4-[(piperazin-4′-yl)-C(O)O—]benzyl,

4-[(1′-Boc-piperazin-4′-yl)-C(O)O—]benzyl,

4-[(4′-acetylpiperazin-1′-yl)C(O)O—]benzyl,

p-[(4′-methanesulfonylpiperazin-1′-yl)-benzyl,

3-nitro-4-[(morpholin-4′-yl)-C(O)O—]benzyl,

4-{[(CH₃)₂NC(S)]₂N—}benzyl,

N-Boc-2-aminoethyl-,

4-[(1,1-dioxothiomorpholin-4-yl)-C(O)O—]benzyl,

4-[(CH₃)₂NS(O)₂—]benzyl,

4-(imidazolid-2′-one-1′-yl)benzyl,

4-[(piperidin-1′-yl)C(O)O—]benzyl,

1-N-benzyl-imidazol4-yl-CH₂—,

3,4-dioxyethylenebenzyl,

3,4-dioxymethylenebenzyl,

4-[-N(SO₂)(CH₃)CH₂CH₂CH₂N(CH₃)₂]benzyl,

4-(3′-formylimidazolid-2′-one-1′-yl)benzyl,

4-[NHC(O)CH(CH₂CH₂CH₂CH₂NH₂)NHBoc]benzyl,

[2′-[4″-hydroxy-4″-(3′″-methoxythien-2′″-yl)piperidin-2″-yl]ethoxy]benzyl,and

p-[(CH₃)₂NCH₂CH₂N(CH₃)C(O)O—]benzyl.

In a preferred embodiment, R⁴ is preferably selected from all possibleisomers arising by substitution with the following groups:

benzyl,

4-aminobenzyl,

4-hydroxybenzyl,

4-nitrobenzyl,

3-chloro-4-hydroxybenzyl,

4-(phenylC(O)NH—)benzyl,

4-(pyridin-4-ylC(O)NH—)benzyl,

4-[(CH₃)₂NC(O)O—]benzyl,

4-[(1′-Cbz-piperidin-4′-yl)C(O)NH—]benzyl,

4-[(piperidin-4′-yl)C(O)NH—]benzyl,

4-[—O-(N-methylpiperidin-4′-yl)]benzyl,

4-[(4′-methylpiperazin-1′-yl)C(O)O—]benzyl,

4-[(4′-(pyridin-2-yl)piperazin-1′-yl)C(O)O—]benzyl,

4-[(thiomorpholin-4′-yl)C(O)O—]benzyl,

3-chloro-4-[(CH₃)₂NC(O)O—]benzyl, and

5-(3-N-benzyl)imidazolyl-CH₂—.

In the compounds of formula IA, R⁵ is preferably2,4-dioxo-tetrahydrofuran-3-yl (3,4-enol), methoxy, ethoxy, iso-propoxy,n-butoxy, t-butoxy, cyclopentoxy, neo-pentoxy,2-α-iso-propyl-4-β-methylcyclohexoxy,2-β-isopropyl-4-β-methylcyclohexoxy, —NH₂, benzyloxy, —NHCH₂COOH,—NHCH₂CH₂COOH, —NH-adamantyl, —NHCH₂CH₂COOCH₂CH₃, —NHSO₂-p-CH₃—φ, —NHOR⁸where R⁸ is hydrogen, methyl, iso-propyl or benzyl, O-(N-succinimidyl),—O-cholest-5-en-3-β-yl, —OCH₂—OC(O)C(CH₃)₃, —O(CH₂)_(z)(NHC(O)R⁹ where zis 1 or 2 and R⁹ is selected from the group consisting of pyrid-3-yl,N-methylpyridyl, and N-methyl-1,4-dihydro-pyrid-3-yl, —NR″C(O)—R′ whereR′ is aryl, heteroaryl or heterocyclic and R″ is hydrogen or—CH₂C(O)OCH₂CH₃.

In the compounds of formula I and IA above, W is preferably oxygen.

Preferred compounds within the scope of formula I and IA above includeby way of example:

N-(benzyl)-L-pyroglutamyl-L-phenylalanine

N-(benzyloxycarbonyl)-L-pyroglutamyl-L-phenylalanine

N-(benzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalanine

N-(3,4-dichlorobenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalanine

N-(3-chlorobenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalanine

N-(3-chlorobenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalaninemethyl ester

N-(4-chlorobenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalanine

N-(4-chlorobenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalaninemethyl ester

N-(4-methylbenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalanine

N-(4-methylbenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalaninemethyl ester

N-(4-methoxybenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalanine

N-(4-methoxybenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalaninemethyl ester

N-(3-chlorobenzyl)-L-pyroglutamyl-L-(N′-benzyl)histidine

N-(4-methylbenzyl)-L-pyroglutamyl-L-(N′-benzyl)histidine methyl ester

N-(4-methylbenzyl)-L-pyroglutamyl-L-(N′-benzyl)histidine

N-(benzyl)-D-pyroglutamyl-L-phenylalanine

N-(4-benzyl-3-oxothiomorpholin-5-carbonyl)-L-phenylalanine

N-(4-benzyl-3-oxothiomorpholin-5-carbonyl)-L-phenylalanine ethyl ester

N-(4-benzyl-3-oxomorpholin-5-carbonyl)-L-phenylalanine

N-(4-benzyl-3-oxothiomorpholin-5-carbonyl)-L-4-nitrophenylalanine methylester

N-(benzyl)-L-pyroglutamyl-L-4-(pyridin-4-ylcarbonylamino)phenylalaninemethyl ester

N-(benzyl)-L-pyroglutamyl-L-4-(1′-benzyloxycarbonylpiperidin-4′-ylcarbonylamino)phenylalaninemethyl ester

N-(benzyl)-L-pyroglutamyl-L-4-(pyridin-4-ylcarbonylamino)phenylalanine

N-(benzyl)-L-pyroglutamyl-L-4-(1′-benzyloxycarbonylpiperidin-4′-ylcarbonylamino)phenylalanine

N-(benzyl)-L-pyroglutamyl-L-tyrosine ethyl ester

N-(benzyl)-L-pyroglutamyl-L-4-(piperidin-4′-ylcarbonylamino)phenylalanine

N-(benzyl)-L-pyroglutamyl-L-4-nitrophenylalanine ethyl ester

N-(benzyl)-L-pyroglutamyl-L-tyrosine

N-(benzyl)-L-pyroglutamyl-L-4-(1′-methylpiperidin-4′-yloxy)phenylalanineethyl ester

N-(benzyl)-L-pyroglutamyl-L-4-nitrophenylalanine

N-(benzyl)-L-pyroglutamyl-L-4-[(4′-methylpiperazin-1′-yl)carbonyloxy]phenylalanineethyl ester

N-(benzyl)-L-pyroglutamyl-L-4-(1′-methylpiperidin-4′-yloxy)phenylalanine

N-(benzyl)-L-pyroglutamyl-L-4-[(4′-methylpiperazin-1′-yl)carbonyloxy]phenylalanine

N-(benzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalanineethyl ester

N-(benzyl)-L-pyroglutamyl-L-4-aminophenylalanine ethyl ester

N-(benzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalanine

N-(benzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalaninetert-butyl ester

N-(benzyl)-L-pyroglutamyl-L-4-[(4′-methylpiperazin-1′-yl)carbonyloxy]phenylalaninetert-butyl ester

N-(benzyl)-L-pyroglutamyl-L-4-[(thiomorpholin-4′-yl)carbonyloxy]phenylalaninetert-butyl ester

N-(4-fluorobenzyl)-L-pyroglutamyl-L-4-[(thiomorpholin-4′-yl)carbonyloxy]phenylalaninetert-butyl ester

N-(benzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalanineisopropyl ester

N-(4-fluorobenzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalaninetert-butyl ester

N-(benzyl)-L-pyroglutamyl-L-3-chloro-4-hydroxyphenylalanine

N-(4-cyanobenzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalaninetert-butyl ester

N-(benzyl)-L-pyroglutamyl-L-3-chloro-4-(N,N-dimethylcarbamyloxy)phenylalaninemethyl ester

N-(4-fluorobenzyl)-L-pyroglutamyl-L-4-[(thiomorpholin-4′-yl)carbonyloxy]phenylalanine

N-(4-cyanobenzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalanine

N-(1-benzyloxycarbonyl-2-imidazolidone-5-carbonyl)-L-4-(N,N-dimethylcarbamyloxy)phenylalanine

N-(4-nitrobenzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalaninetert-butyl ester

N-(benzyl)-L-pyroglutamyl-L-3-chloro-4-(N,N-dimethylcarbamyloxy)phenylalanine

N-(4-fluorobenzyl)-L-pyroglutamyl-L-4-[(4′-(pyridin-2-yl)piperazin-1′-yl)carbonyloxy]phenylalanine

N-(4-fluorobenzyl)-L-pyroglutamyl-L-4-[(4′-(pyridin-2-yl)piperazin-1′-yl)carbonyloxy]phenylalaninetert-butyl ester

N-(4-aminobenzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalaninetert-butyl ester

N-(pyridin-3-ylmethyl)-L-pyroglutamyl-L-tyrosine tert-butyl ester

N-(pyridin-3-ylmethyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalanine

N-(pyridin-3-ylmethyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalaninetert-butyl ester

N-(pyridin-3-ylmethyl)-L-pyroglutamyl-L-4-[(4′-(pyridin-2-yl)piperazin-1′-yl)carbonyloxy]phenylalaninetert-butyl ester

N-(pyridin-3-ylmethyl)-L-pyroglutamyl-L-4-[(4′-(pyridin-2-yl)piperazin-1′-yl)carbonyloxy]phenylalanine

N-(4-benzyl-5-oxo-4-azatricyclo[4.2.1.0(3,7)]nonane-3-carbonyl)-L-tyrosinetert-butyl ester

N-(4-benzyl-5-oxo-4-azatricyclo[4.2.1.0(3,7)]nonane-3-carbonyl)-L-4-(N,N-dimethylcarbamyloxy)phenylalaninetert-butyl ester

N-(4-benzyl-5-oxo-4-azatricyclo[4.2.1.0(3,7)]nonane-3-carbonyl)-L-4-(N,N-dimethylcarbamyloxy)phenylalanine

N-(4-fluorobenzyl)-t-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalanine

and pharmaceutically acceptable salts thereof as well as any of theester compounds recited above wherein one ester is replaced with anotherester selected from the group consisting of methyl ester, ethyl ester,n-propyl ester, isopropyl ester, n-butyl ester, isobutyl ester,sec-butyl ester and tert-butyl ester.

This invention also provides methods for binding VLA-4 in a biologicalsample which method comprises contacting the biological sample with acompound of formula I or IA above under conditions wherein said compoundbinds to VLA-4.

Certain of the compounds of formula I and IA above are also useful inreducing VLA-4 mediated inflammation in vivo.

This invention also provides pharmaceutical compositions comprising apharmaceutically acceptable carrier and a therapeutically effectiveamount of one or more of the compounds of formula I or IA above.Alternatively, racemic mixtures can be used.

The pharmaceutical compositions may be used to treat VLA4 mediateddisease conditions. Such disease conditions include, by way of example,asthma, Alzheimer's disease, atherosclerosis, AIDS dementia, diabetes(including acute juvenile onset diabetes), inflammatory bowel disease(including ulcerative colitis and Crohn's disease), multiple sclerosis,rheumatoid arthritis, tissue transplantation, tumor metastasis,meningitis, encephalitis, stroke, and other cerebral traumas, nephritis,retinitis, atopic dermatitis, psoriasis, myocardial ischemia and acuteleukocyte-mediated lung injury such as that which occurs in adultrespiratory distress syndrome.

Accordingly, this invention also provides methods for the treatment ofan inflammatory disease in a patient mediated by VLA-4 which methodscomprise administering to the patient the pharmaceutical compositionsdescribed above.

Preferred compounds of formula I and IA above include those set forth inTables IA, IB, IC and ID below:

TABLE IA

R^(a) R^(b) R^(c) φ-CH₂— φ-CH₂— —OH φ-CH₂—OC(O)— φ-CH₂— —OH φ-CH₂—4-[φ-C(O)NH benzyl- —OH 3,4-dichlorobenzyl- 4-[φ-C(O)NH benzyl- —OH4-chlorobenzyl- 4-[φ-C(O)NH benzyl- —OH 3-chlorobenzyl-4-[φ-C(O)NH benzyl- —OCH₃ 3-chlorobenzyl- 4-[φ-C(O)NH benzyl- —OH4-chlorobenzyl- 4-[φ-C(O)NH benzyl- —OCH₃ 4-CH₃-benzyl-4-[φ-C(O)NH benzyl- —OCH₃ 4-CH₃-benzyl- 4-[φ-C(O)NH benzyl- —OH4-CH₃O-benzyl- 4-[φ-C(O)NH benzyl- —OCH₃ 4-CH₃O-benzyl-4-[φ-C(O)NH benzyl- —OH 3-chlorobenzyl- (1-benzylimidazol-4-yl)methyl-—OH 4-CH₃-benzyl- (1-benzylimidazol-4-yl)methyl- —OCH₃ 4-CH₃-benzyl-(1-benzylimidazol-4-yl)methyl- —OH φ-CH₂— φ-CH₂— —OH φ-CH₂—4-[pyridin-4-yl-C(O)NH]-benzyl- —OCH₃ φ-CH₂—4-[(1-(benzyloxy-C(O)-)piper- —OCH₃ idin-4-yl-)C(O)NH benzyl- φ-CH₂—4-[(pyridin-4- —OH yl-)C(O)NH benzyl- φ-CH₂—4-[(1-(benzyloxy-C(O)-)piper- —OH idin-4-yl-)C(O)NH benzyl- φ-CH₂—4-hydroxybenzyl- —OCH₂CH₃ φ-CH₂— 4-[(piper- —OHidin-4-yl-)C(O)NH-]benzyl- φ-CH₂— 4-NO₂-benzyl- —OCH₂CH₃ φ-CH₂—4-hydroxybenzyl- —OH φ-CH₂— 4-[(1-methylpiperidin-4- —OCH₂CH₃yl-)O-]benzyl- φ-CH₂— 4-NO₂-benzyl- —OH φ-CH₂— 4-[(4-methylpiperazin-1-—OCH₂CH₃ yl-)C(O)O-]benzyl- φ-CH₂— 4-[(1-methylpiperidin-4- —OHyl-)O-]benzyl- φ-CH₂— 4-[(4-methylpiperazin-1- —OH yl-)C(O)O-]benzyl-φ-CH₂— 4-[(CH₃)₂NC(O)O-]benzyl- —OCH₂CH₃ φ-CH₂— 4-NH₂-benzyl- —OCH₂CH₃φ-CH₂— 4-[(CH₃)₂NC(O)O-]benzyl- —OH φ-CH₂— 4-[(CH₃)₂NC(O)O-]benzyl-—OC(CH₃)₃ φ-CH₂— 4-[(4-methylpiperazin-1- —OC(CH₃)₃ yl-)C(O)O-]benzyl-φ-CH₂— 4-[thiomorpholin-4- —OC(CH₃)₃ yl-C(O)O-]benzyl- 4-fluoro-benzyl-4-[thiomorpholin-4- —OC(CH₃)₃ yl-C(O)O-]benzyl- φ-CH₂—4-[(CH₂)₃NC(O)O-]benzyl- —OCH(CH₃)₂ 4-fluoro-benzyl-4-[(CH₂)₃NC(O)O-]benzyl- —OC(CH₃)₃ φ-CH₂— 3-chloro-4-hydroxybenzyl-—OCH₃ 4-cyano-benzyl- 4-[(CH₂)₃NC(O)O-]benzyl- —OC(CH₃)₃ φ-CH₂—3-chloro-4- —OCH₃ [(CH₂)₃NC(O)O-]benzyl- 4-fluoro-benzyl-4-[(CH₂)₃NC(O)O-]benzy1- —OH 4-fluoro-benzyl- 4-[thiomorpholin-4- —OHyl-C(O)O-]benzyl- 4-cyano-benzyl- 4-[(CH₂)₃NC(O)O-]benzyl- —OH4-NO₂-benzyl- 4-[(CH₂)₃NC(O)O-]benzyl- —OC(CH₃)₃ φ-CH₂— 3-chloro-4- —OH[(CH₂)₃NC(O)O-]benzyl- 4-fluoro-benzyl- 4-[4-(pyridin-2-yl)piper- —OHazin-1-yl-C(O)O-]benzyl- 4-fluoro-benzyl- 4-[4-(pyridin-2-yl)piper-—OC(CH₃)₃ azin-1-yl-C(O)O-]benzyl- 4-NH₂-benzyl-4-[(CH₂)₃NC(O)O-]benzyl- —OC(CH₃)₃ pyridin-3-CH₂—4-[(CH₂)₃NC(O)O-]benzyl- —OH pyridin-3-CH₂— 4-[4-(pyridin-2-yl)piper-—OC(CH₃)₃ pyridin-3-CH₂— 4-[4-(pyridin-2-yl)piper- —OHazin-1-yl-C(O)O-]benzyl-

TABLE IB

R^(d) R^(e) R^(f) A φ-CH₂— φ-CH₂— —OH S φ-CH₂— φ-CH₂— —OCH₂CH₃ S φ-CH₂—φ-CH₂— —OH O φ-CH₂— 4-NO₂-benzyl- —OCH₃ S

TABLE IC

R^(g) R^(h) R^(i) φ-CH₂—OC(O)— 4-[(CH₂)₃NC(O)O-]benzyl- —OH

TABLE ID

R^(j) R^(k) R^(l) φ-CH₂— 4-hydroxybenzyl- —OC(CH₃)₃ φ-CH₂—4-[(CH₂)₃NC(O)O-]benzyl- —OC(CH₃)₃ φ-CH₂— 4-[(CH₂)₃NC(O)O-]benzyl- —OH

DETAILED DESCRIPTION OF THE INVENTION

As above, this invention relates to compounds which inhibit leukocyteadhesion and, in particular, leukocyte adhesion mediated by VLA-4.However, prior to describing this invention in further detail, thefollowing terms will first be defined.

Definitions

As used herein, “alkyl” refers to alkyl groups preferably having from 1to 10 carbon atoms and more preferably 1 to 6 carbon atoms. This term isexemplified by groups such as methyl, t-butyl, n-heptyl, octyl and thelike.

“Substituted alkyl” refers to an alkyl group, preferably of from 1 to 10carbon atoms, having from 1 to 5 substituents selected from the groupconsisting of alkoxy, substituted alkoxy, acyl, acylamino,thiocarbonylamino, acyloxy, amino, amidino, alkyl amidino, thioamidino,aminoacyl, aminocarbonylamino, aminothiocarbonylamino, aminocarbonyloxy,aryl, substituted aryl, aryloxy, substituted aryloxy, aryloxylaryl,substituted aryloxyaryl, cyano, halogen, hydroxyl, nitro, carboxyl,carboxylalkyl, carboxyl-substituted alkyl, carboxyl-cycloalkyl,carboxyl-substituted cycloalkyl, carboxylaryl, carboxyl-substitutedaryl, carboxylheteroaryl, carboxyl-substituted heteroaryl,carboxylheterocyclic, carboxyl-substituted heterocyclic, cycloalkyl,substituted cycloalkyl, guanidino, guanidinosulfone, thiol, thioalkyl,substituted thioalkyl, thioaryl, substituted thioaryl, thiocycloalkyl,substituted thiocycloalkyl, thioheteroaryl, substituted thioheteroaryl,thioheterocyclic, substituted thioheterocyclic, heteroaryl, substitutedaryl, substituted heteroaryl, heterocyclic, substituted heterocyclic,cycloalkoxy, substituted cycloalkoxy, heteroaryloxy, substitutedheteroaryloxy, heterocyclyloxy, substituted heterocyclyloxy,oxycarbonylamino, oxythiocarbonylamino, —OS(O)₂-alkyl,—OS(O)₂-substituted alkyl, —OS(O)₂-aryl, —OS(O)₂-substituted aryl,—OS(O)₂-heteroaryl, —OS(O)₂-substituted heteroaryl,—OS(O)₂-heterocyclic, —OS(O)₂-substituted heterocyclic, —OSO₂—NRR whereR is hydrogen or alkyl, —NRS(O)₂-alkyl, —NRS(O)₂-substituted alkyl,—NRS(O)₂-aryl, —NRS(O)₂-substituted aryl, —NRS(O)₂-heteroaryl,—NRS(O)₂-substituted heteroaryl, —NRS(O)₂-heterocyclic,—NRS(O)₂-substituted heterocyclic, —NRS(O)₂—NR—alkyl,—NRS(O)₂—NR-substituted alkyl, —NRS(O)₂—NR-aryl, —NRS(O)₂—NR-substitutedaryl, —NRS(O)₂—NR-heteroaryl, —NRS(O)₂—NR-substituted heteroaryl,—NRS(O)₂—NR-heterocyclic, —NRS(O)₂—NR-substituted heterocyclic where Ris hydrogen or alkyl, mono- and di-alkylamino, mono- and di-(substitutedalkyl)amino, mono- and di-arylamino, mono- and di-substituted arylamino,mono- and di-heteroarylamino, mono- and di-substituted heteroarylamino,mono- and di-heterocyclic amino, mono- and di-substituted heterocyclicamino, unsymmetric di-substituted amines having different substituentsselected from alkyl, substituted alkyl, aryl, substituted aryl,heteroaryl, substituted heteroaryl, heterocyclic and substitutedheterocyclic and substituted alkyl groups having amino groups blocked byconventional blocking groups such as Boc, Cbz, formyl, and the like oralkyl/substituted alkyl groups substituted with —SO₂-alkyl,—SO₂-substituted alkyl, —SO₂-alkenyl, —SO₂-substituted alkenyl,—SO₂-cycloalkyl, —SO₂-substituted cycloalkyl, —SO₂-aryl,—SO₂-substituted aryl, —SO₂-heteroaryl, —SO₂-substituted heteroaryl,—SO₂-heterocyclic, —SO₂-substituted heterocyclic and —SO₂NRR where R ishydrogen or alkyl.

“Alkylene” refers to a divalent hydrocarbon radical of the formula—(CH₂)_(n)— where n is an integer ranging from 1 to 10. By way ofillustration, the term alkylene includes methylene (—CH₂—), ethylene(—CH₂CH₂—), propylene (—CH₂CH₂CH₂—) and the like.

“Substituted alkylene” refers to an alkylene group, preferably of from 1to 10 carbon atoms, having from 1 to 5 substituents selected from thegroup consisting of alkoxy, substituted alkoxy, acyl, acylamino,thiocarbonylamino, acyloxy, amino, amidino, alkyl amidino, thioamidino,aminoacyl, aminocarbonylamino, aminothiocarbonylamino, aminocarbonyloxy,aryl, substituted aryl, aryloxy, substituted aryloxy, aryloxylaryl,substituted aryloxyaryl, cyano, halogen, hydroxyl, nitro, carboxyl,carboxylalkyl, carboxyl-substituted alkyl, carboxyl-cycloalkyl,carboxyl-substituted cycloalkyl, carboxylaryl, carboxyl-substitutedaryl, carboxylheteroaryl, carboxyl-substituted heteroaryl,carboxylheterocyclic, carboxyl-substituted heterocyclic, cycloalkyl,substituted cycloalkyl, guanidino, guanidinosulfone, thiol, thioalkyl,substituted thioalkyl, thioaryl, substituted thioaryl, thiocycloalkyl,substituted thiocycloalkyl, thioheteroaryl, substituted thioheteroaryl,thioheterocyclic, substituted thioheterocyclic, heteroaryl, substitutedaryl, substituted heteroaryl, heterocyclic, substituted heterocyclic,cycloalkoxy, substituted cycloalkoxy, heteroaryloxy, substitutedheteroaryloxy, heterocyclyloxy, substituted heterocyclyloxy,oxycarbonylamino, oxythiocarbonylamino, —OS(O)₂-alkyl,—OS(O)₂-substituted alkyl, —OS(O)₂-aryl, —OS(O)₂-substituted aryl,—OS(O)₂-heteroaryl, —OS(O)₂-substituted heteroaryl,—OS(O)₂-heterocyclic, —OS(O)₂-substituted heterocyclic, —OSO₂—NRR whereR is hydrogen or alkyl, —NRS(O)₂-alkyl, —NRS(O)₂-substituted alkyl,—NRS(O)₂-aryl, —NRS(O)₂-substituted aryl, —NRS(O)₂-heteroaryl,—NRS(O)₂-substituted heteroaryl, —NRS(O)₂-heterocyclic,—NRS(O)₂-substituted heterocyclic, —NRS(O)₂—NR-alkyl,—NRS(O)₂—NR-substituted alkyl, —NRS(O)₂—NR-aryl, —NRS(O)₂—NR-substitutedaryl, —NRS(O)₂—NR-heteroaryl, —NRS(O)₂—NR-substituted heteroaryl,—NRS(O)₂—NR-heterocyclic, —NRS(O)₂—NR-substituted heterocyclic where Ris hydrogen or alkyl, mono- and di-alkylamino, mono- and di-(substitutedalkyl)amino, mono- and di-arylamino, mono- and di-substituted arylamino,mono- and di-heteroarylamino, mono- and di-substituted heteroarylamino,mono- and di-heterocyclic amino, mono- and di-substituted heterocyclicamino, unsymmetric di-substituted amines having different substituentsselected from alkyl, substituted alkyl, aryl, substituted aryl,heteroaryl, substituted heteroaryl, heterocyclic and substitutedheterocyclic and substituted alkyl groups having amino groups blocked byconventional blocking groups such as Boc, Cbz, formyl, and the like oralkyl/substituted alkyl groups substituted with —SO₂-alkyl,—SO₂-substituted alkyl, —SO₂-alkenyl, —SO₂-substituted alkenyl,—SO₂-cycloalkyl, —SO₂-substituted cycloalkyl, —SO₂-aryl,—SO₂-substituted aryl, —SO₂-heteroaryl, —SO₂-substituted heteroaryl,—SO₂-heterocyclic, —SO₂-substituted heterocyclic and —SO₂NRR where R ishydrogen or alkyl. Additionally, two or more substituents on thesubstituted alkylene group may also be joined together to form a fusedand/or bridged cycloalkyl, substituted cycloalkyl, heterocyclic orsubstituted heterocyclic group, or a fused aryl or heteroaryl group.

“Alkoxy” refers to the group “alkyl-O-” which includes, by way ofexample, methoxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy, tert-butoxy,sec-butoxy, n-pentoxy, n-hexoxy, 1,2-dimethylbutoxy, and the like.

“Substituted alkoxy” refers to the group “substituted alkyl-O-”.

“Alkoxycarbonyl” refers to the group “alkyl-O—C(O)—”.

“Substituted alkoxycarbonyl” refers to the group “substitutedalkyl-O—C(O)—”.

“Acyl” refers to the groups H—C(O)—, alkyl-C(O)—, substitutedalkyl-C(O)—, alkenyl-C(O)—, substituted alkenyl-C(O)—, alkynyl-C(O)—,substituted alkynyl-C(O)—, cycloalkyl-C(O)—, substitutedcycloalkyl-C(O)—, aryl-C(O)—, substituted aryl-C(O)—, heteroaryl-C(O)—,substituted heteroaryl-C(O), heterocyclic-C(O)—, and substitutedheterocyclic-C(O)— wherein alkyl, substituted alkyl, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, aryl, substituted aryl, heteroaryl, substitutedheteroaryl, heterocyclic and substituted heterocyclic are as definedherein.

“Acylamino” refers to the group —C(O)NRR where each R is independentlyselected from the group consisting of hydrogen, alkyl, substitutedalkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, aryl,substituted aryl, cycloalkyl, substituted cycloalkyl, heteroaryl,substituted heteroaryl, heterocyclic, substituted heterocyclic and whereeach R is joined to form together with the nitrogen atom a heterocyclicor substituted heterocyclic ring wherein alkyl, substituted alkyl,alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, aryl, substituted aryl, heteroaryl, substitutedheteroaryl, heterocyclic and substituted heterocyclic are as definedherein.

“Thiocarbonylamino” refers to the group —C(S)NRR where each R isindependently selected from the group consisting of hydrogen, alkyl,substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substitutedalkynyl, aryl, substituted aryl, cycloalkyl, substituted cycloalkyl,heteroaryl, substituted heteroaryl, heterocyclic, substitutedheterocyclic and where each R is joined to form, together with thenitrogen atom a heterocyclic or substituted heterocyclic ring whereinalkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl,substituted alkynyl, cycloalkyl, substituted cycloalkyl, aryl,substituted aryl, heteroaryl, substituted heteroaryl, heterocyclic andsubstituted heterocyclic are as defined herein.

“Acyloxy” refers to the groups alkyl-C(O)O—, substituted alkyl-C(O)O—,alkenyl-C(O)O—, substituted alkenyl-C(O)O—, alkynyl-C(O)O—, substitutedalkynyl-C(O)O—, aryl-C(O)O—, substituted aryl-C(O)O—, cycloalkyl-C(O)O—,substituted cycloalkyl-C(O)O—, heteroaryl-C(O)O—, substitutedheteroaryl-C(O)O—, heterocyclic-C(O)O—, and substitutedheterocyclic-C(O)O—, wherein alkyl, substituted alkyl, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, aryl, substituted aryl, heteroaryl, substitutedheteroaryl, heterocyclic and substituted heterocyclic are as definedherein.

“Alkenyl” refers to alkenyl group preferably having from 2 to 10 carbonatoms and more preferably 2 to 6 carbon atoms and having at least 1 andpreferably from 1-2 sites of alkenyl unsaturation.

“Substituted alkenyl” refers to alkenyl groups having from 1 to 5substituents selected from the group consisting of alkoxy, substitutedalkoxy, acyl, acylamino, thiocarbonylamino, acyloxy, amino, amidino,alkylamidino, thioamidino, aminoacyl, aminocarbonylamino,aminothiocarbonylamino, aminocarbonyloxy, aryl, substituted aryl,aryloxy, substituted aryloxy, aryloxyaryl, substituted aryloxyaryl,halogen, hydroxyl, cyano, nitro, carboxyl, carboxylalkyl,carboxyl-substituted alkyl, carboxylcycloalkyl, carboxyl-substitutedcycloalkyl, carboxylaryl, carboxyl-substituted aryl, carboxylheteroaryl,carboxyl-substituted heteroaryl, carboxylheterocyclic,carboxyl-substituted heterocyclic, cycloalkyl, substituted cycloalkyl,guanidino, guanidinosulfone, thiol, thioalkyl, substituted thioalkyl,thioaryl, substituted thioaryl, thiocycloalkyl, substitutedthiocycloalkyl, thioheteroaryl, substituted thioheteroaryl,thioheterocyclic, substituted thioheterocyclic, heteroaryl, substitutedheteroaryl, heterocyclic, substituted heterocyclic, cycloalkoxy,substituted cycloalkoxy, heteroaryloxy, substituted heteroaryloxy,heterocyclyloxy, substituted heterocyclyloxy, oxycarbonylamino,oxythiocarbonylamino, —OS(O)₂-alkyl, —OS(O)₂-substituted alkyl,—OS(O)₂-aryl, —OS(O)₂-substituted aryl, —OS(O)₂-heteroaryl,—OS(O)₂-substituted heteroaryl, —OS(O)₂-heterocyclic,—OS(O)₂-substituted heterocyclic, —OSO₂—NRR where R is hydrogen oralkyl, —NRS(O)₂-alkyl, —NRS(O)₂-substituted alkyl, —NRS(O)₂-aryl,—NRS(O)₂-substituted aryl, —NRS(O)₂-heteroaryl, —NRS(O)₂-substitutedheteroaryl, —NRS(O)₂-heterocyclic, —NRS(O)₂-substituted heterocyclic,—NRS(O)₂—NR-alkyl, —NRS(O)₂—NR-substituted alkyl, —NRS(O)₂—NR-aryl,—NRS(O)₂—NR-substituted aryl, —NRS(O)₂—NR-heteroaryl,—NRS(O)₂—NR-substituted heteroaryl, —NRS(O)₂—NR-heterocyclic,—NRS(O)₂—NR-substituted heterocyclic where R is hydrogen or alkyl, mono-and di-alkylamino, mono- and di-(substituted alkyl)amino, mono- anddi-arylamino, mono- and di-substituted arylamino, mono- anddi-heteroarylamino, mono- and di-substituted heteroarylamino, mono- anddi-heterocyclic amino, mono- and di-substituted heterocyclic amino,unsymmetric di-substituted amines having different substituents selectedfrom alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl,substituted heteroaryl, heterocyclic and substituted heterocyclic andsubstituted alkenyl groups having amino groups blocked by conventionalblocking groups such as Boc, Cbz, formyl, and the like oralkenyl/substituted alkenyl groups substituted with —SO₂-alkyl,—SO₂-substituted alkyl, —SO₂-alkenyl, —SO₂-substituted alkenyl,—SO₂-cycloalkyl, —SO₂-substituted cycloalkyl, —SO₂-aryl,—SO₂-substituted aryl, —SO₂-heteroaryl, —SO₂-substituted heteroaryl,—SO₂-heterocyclic, —SO₂-substituted heterocyclic and —SO₂NRR where R ishydrogen or alkyl.

“Alkynyl” refers to alkynyl group preferably having from 2 to 10 carbonatoms and more preferably 3 to 6 carbon atoms and having at least 1 andpreferably from 1-2 sites of alkynyl unsaturation.

“Substituted alkynyl” refers to alkynyl groups having from 1 to 5substituents selected from the group consisting of alkoxy, substitutedalkoxy, acyl, acylamino, thiocarbonylamino, acyloxy, amino, amidino,alkylamidino, thioamidino, aminoacyl, aminocarbonylamino,aminothiocarbonylamino, aminocarbonyloxy, aryl, substituted aryl,aryloxy, substituted aryloxy, aryloxyaryl, substituted aryloxyaryl,halogen, hydroxyl, cyano, nitro, carboxyl, carboxylalkyl,carboxyl-substituted alkyl, carboxylcycloalkyl, carboxyl-substitutedcycloalkyl, carboxylaryl, carboxyl-substituted aryl, carboxylheteroaryl,carboxyl-substituted heteroaryl, carboxylheterocyclic,carboxyl-substituted heterocyclic, cycloalkyl, substituted cycloalkyl,guanidino, guanidinosulfone, thiol, thioalkyl, substituted thioalkyl,thioaryl, substituted thioaryl, thiocycloalkyl, substitutedthiocycloalkyl, thioheteroaryl, substituted thioheteroaryl,thioheterocyclic, substituted thioheterocyclic, heteroaryl, substitutedheteroaryl, heterocyclic, substituted heterocyclic, cycloalkoxy,substituted cycloalkoxy, heteroaryloxy, substituted heteroaryloxy,heterocyclyloxy, substituted heterocyclyloxy, oxycarbonylamino,oxythiocarbonylamino, —OS(O)₂-alkyl, —OS(O)₂-substituted alkyl,—OS(O)₂-aryl, —OS(O)₂-substituted aryl, —OS(O)₂-heteroaryl,—OS(O)₂-substituted heteroaryl, —OS(O)₂-heterocyclic,—OS(O)₂-substituted heterocyclic, —OSO₂—NRR where R is hydrogen oralkyl, —NRS(O)₂-alkyl, —NRS(O)₂-substituted alkyl, —NRS(O)₂-aryl,—NRS(O)₂-substituted aryl, —NRS(O)₂-heteroaryl, —NRS(O)₂-substitutedheteroaryl, —NRS(O)₂-heterocyclic, —NRS(O)₂-substituted heterocyclic,—NRS(O)₂—NR-alkyl, —NRS(O)₂—NR-substituted alkyl, —NRS(O)₂—NR-aryl,—NRS(O)₂—NR-substituted aryl, —NRS(O)₂—NR-heteroaryl,—NRS(O)₂—NR-substituted heteroaryl, —NRS(O)₂—NR-heterocyclic,—NRS(O)₂—NR-substituted heterocyclic where R is hydrogen or alkyl, mono-and di-alkylamino, mono- and di-(substituted alkyl)amino, mono- anddi-arylamino, mono- and di-substituted arylamino, mono- anddi-heteroarylamino, mono- and di-substituted heteroarylamino, mono- anddi-heterocyclic amino, mono- and di-substituted heterocyclic amino,unsymmetric di-substituted amines having different substituents selectedfrom alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl,substituted heteroaryl, heterocyclic and substituted heterocyclic andsubstituted alkynyl groups having amino groups blocked by conventionalblocking groups such as Boc, Cbz, formyl, and the like oralkynyl/substituted alkynyl groups substituted with —SO₂-alkyl,—SO₂-substituted alkyl, —SO₂-alkenyl, —SO₂-substituted alkenyl,—SO₂-cycloalkyl, —SO₂-substituted cycloalkyl, —SO₂-aryl,—SO₂-substituted aryl, —SO₂-heteroaryl, —SO₂-substituted heteroaryl,—SO₂-heterocyclic, —SO₂-substituted heterocyclic and —SO₂NRR where R ishydrogen or alkyl.

“Amidino” refers to the group H₂NC(═NH)— and the term “alkylamidino”refers to compounds having 1 to 3 alkyl groups (e.g., alkyl-HNC(═NH)—and the like).

“Thioamidino” refers to the group RSC(═NH)— where R is hydrogen oralkyl.

“Aminoacyl” refers to the groups —NRC(O)alkyl, —NRC(O)substituted alkyl,—NRC(O)cycloalkyl, —NRC(O)substituted cycloalkyl, —NRC(O)alkenyl,—NRC(O)substituted alkenyl, —NRC(O)alkynyl, —NRC(O)substituted alkynyl,—NRC(O)aryl, —NRC(O)substituted aryl, —NRC(O)heteroaryl,—NRC(O)substituted heteroaryl, —NRC(O)heterocyclic, and—NRC(O)substituted heterocyclic where R is hydrogen or alkyl and whereinalkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl,substituted alkynyl, cycloalkyl, substituted cycloalkyl, aryl,substituted aryl, heteroaryl, substituted heteroaryl, heterocyclic andsubstituted heterocyclic are as defined herein.

“Aminocarbonyloxy” refers to the groups —NRC(O)O-alkyl,—RC(O)O-substituted alkyl, —NRC(O)O-alkenyl, —NRC(O)O-substitutedalkenyl, —NRC(O)O-alkynyl, —NRC(O)O-substituted alkynyl,—NRC(O)O-cycloalkyl, —NRC(O)O-substituted cycloalkyl, —NRC(O)O-aryl,—NRC(O)O-substituted aryl, —NRC(O)O-heteroaryl, —NRC(O)O-substitutedheteroaryl, —NRC(O)O-heterocyclic, and —NRC(O)O-substituted heterocyclicwhere R is hydrogen or alkyl and wherein alkyl, substituted alkyl,alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, aryl, substituted aryl, heteroaryl, substitutedheteroaryl, heterocyclic and substituted heterocyclic are as definedherein.

“Oxycarbonylamino” refers to the groups —OC(O)NH₂, —OC(O)NRR,—OC(O)NR-alkyl, —OC(O)NR-substituted alkyl, —OC(O)NR-alkenyl,—OC(O)NR-substituted alkenyl, —OC(O)NR-alkynyl, —OC(O)NR-substitutedalkynyl, —OC(O)NR-cycloalkyl, —OC(O)NR-substituted cycloalkyl,—OC(O)NR-aryl, —OC(O)NR-substituted aryl, —OC(O)NR-heteroaryl,—OC(O)NR-substituted heteroaryl, —OC(O)NR-heterocyclic, and—OC(O)NR-substituted heterocyclic where R is hydrogen, alkyl or whereeach R is joined to form, together with the nitrogen atom, aheterocyclic or substituted heterocyclic ring, and wherein alkyl,substituted alkyl, alkenyl, substituted alkenyl, alkynyl, substitutedalkynyl, cycloalkyl, substituted cycloalkyl, aryl, substituted aryl,heteroaryl, substituted heteroaryl, heterocyclic and substitutedheterocyclic are as defined herein.

“Oxythiocarbonylamino” refers to the groups —OC(S)NH₂, —OC(S)NRR,—OC(S)NR-alkyl, —OC(S)NR-substituted alkyl, —OC(S)NR-alkenyl,—OC(S)NR-substituted alkenyl, —OC(S)NR-alkynyl, —OC(S)NR-substitutedalkynyl, —OC(S)NR-cycloalkyl, —OC(S)NR-substituted cycloalkyl,—OC(S)NR-aryl, —OC(S)NR-substituted aryl, —OC(S)NR-heteroaryl,—OC(S)NR-substituted heteroaryl, —OC(S)NR-heterocyclic, and—OC(S)NR-substituted heterocyclic where R is hydrogen, alkyl or whereeach R is joined to form together with the nitrogen atom, a heterocyclicor substituted heterocyclic ring, and wherein alkyl, substituted alkyl,alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, aryl, substituted aryl, heteroaryl, substitutedheteroaryl, heterocyclic and substituted heterocyclic are as definedherein.

“Aminocarbonylamino” refers to the groups —NRC(O)NRR, —NRC(O)NR-alkyl,—NRC(O)NR-substituted alkyl, —NRC(O)NR-alkenyl, —NRC(O)NR-substitutedalkenyl, —NRC(O)NR-alkynyl, —NRC(O)NR-substituted alkynyl,—NRC(O)NR-aryl, —NRC(O)NR-substituted aryl, —NRC(O)NR-cycloalkyl,—NRC(O)NR-substituted cycloalkyl, —NRC(O)NR-heteroaryl, and—NRC(O)NR-substituted heteroaryl, —NRC(O)NR-heterocyclic, and—NRC(O)NR-substituted heterocyclic where each R is independentlyhydrogen, alkyl or where each R is joined to form together with thenitrogen atom a heterocyclic or substituted heterocyclic ring as well aswhere one of the amino groups is blocked by conventional blocking groupssuch as Boc, Cbz, formyl, and the like and wherein alkyl, substitutedalkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl,cycloalkyl, substituted cycloalkyl, aryl, substituted aryl, heteroaryl,substituted heteroaryl, heterocyclic and substituted heterocyclic are asdefined herein.

“Aminothiocarbonylamino” refers to the groups —NRC(S)NRR,—NRC(S)NR-alkyl, —NRC(S)NR-substituted alkyl, —NRC(S)NR-alkenyl,—NRC(S)NR-substituted alkenyl, —NRC(S)NR-alkynyl, —NRC(S)NR-substitutedalkynyl, —NRC(S)NR-aryl, —NRC(S)NR-substituted aryl,—NRC(S)NR-cycloalkyl, —NRC(S)NR-substituted cycloalkyl,—NRC(S)NR-heteroaryl, and —NRC(S)NR-substituted heteroaryl,—NRC(S)NR-heterocyclic, and —NRC(S)NR-substituted heterocyclic whereeach R is independently hydrogen, alkyl or where each R is joined toform together with the nitrogen atom a heterocyclic or substitutedheterocyclic ring as well as where one of the amino groups is blocked byconventional blocking groups such as Boc, Cbz, formyl, and the like, andwherein alkyl, substituted alkyl, alkenyl, substituted alkenyl, alkynyl,substituted alkynyl, cycloalkyl, substituted cycloalkyl, aryl,substituted aryl, heteroaryl, substituted heteroaryl, heterocyclic andsubstituted heterocyclic are as defined herein.

“Aryl” or “Ar” refers to an unsaturated aromatic carbocyclic group offrom 6 to 14 carbon atoms having a single ring (e.g., phenyl) ormultiple condensed rings (e.g., naphthyl or anthryl) which condensedrings may or may not be aromatic (e.g., 2-benzoxazolinone,2H-1,4-benzoxazin-3(4H)-one-7yl, and the like). Preferred aryls includephenyl and naphthyl.

Substituted aryl refers to aryl groups which are substituted with from 1to 3 substituents selected from the group consisting of hydroxy, acyl,acylamino, thiocarbonylamino, acyloxy, alkyl, substituted alkyl, alkoxy,substituted alkoxy, alkenyl, substituted alkenyl, alkynyl, substitutedalkynyl, amidino, alkylamidino, thioamidino, amino, aminoacyl,aminocarbonyloxy, aminocarbonylamino, aminothiocarbonylamino, aryl,substituted aryl, aryloxy, substituted aryloxy, cycloalkoxy, substitutedcycloalkoxy, heteroaryloxy, substituted heteroaryloxy, heterocyclyloxy,substituted heterocyclyloxy, carboxyl, carboxylalkyl,carboxyl-substituted alkyl, carboxyl-cycloalkyl, carboxyl-substitutedcycloalkyl, carboxylaryl, carboxyl-substituted aryl, carboxylheteroaryl,carboxyl-substituted heteroaryl, carboxylheterocyclic,carboxyl-substituted heterocyclic, carboxylamido, cyano, thiol,thioalkyl, substituted thioalkyl, thioaryl, substituted thioaryl,thioheteroaryl, substituted thioheteroaryl, thiocycloalkyl, substitutedthiocycloalkyl, thioheterocyclic, substituted thioheterocyclic,cycloalkyl, substituted cycloalkyl, guanidino, guanidinosulfone, halo,nitro, heteroaryl, substituted heteroaryl, heterocyclic, substitutedheterocyclic, cycloalkoxy, substituted cycloalkoxy, heteroaryloxy,substituted heteroaryloxy, heterocyclyloxy, substituted heterocyclyloxy,oxycarbonylamino, oxythiocarbonylamino, —S(O)₂-alkyl, —S(O)₂-substitutedalkyl, —S(O)2-cycloalkyl, —S(O)₂-substituted cycloalkyl, —S(O)₂-alkenyl,—S(O)₂-substituted alkenyl, —S(O)₂-aryl, —S(O)₂-substituted aryl,—S(O)₂-heteroaryl, —S(O)₂-substituted heteroaryl, —S(O)₂-heterocyclic,—S(O)₂-substituted heterocyclic, —OS(O)₂-alkyl, —OS(O)₂-substitutedalkyl, —OS(O)₂-aryl, —OS(O)₂-substituted aryl, —OS(O)₂-heteroaryl,—OS(O)₂-substituted heteroaryl, —OS(O)2-heterocyclic,—OS(O)₂-substituted heterocyclic, —OSO₂—NRR where R is hydrogen oralkyl, —NRS(O)₂-alkyl, —NRS(O)₂-substituted alkyl, —NRS(O)₂-aryl,—NRS(O)₂-substituted aryl, —NRS(O)₂-heteroaryl, —NRS(O)₂-substitutedheteroaryl, —NRS(O)₂-heterocyclic, —NRS(O)₂-substituted heterocyclic,—NRS(O)₂—NR-alkyl, —NRS(O)₂—NR-substituted alkyl, —NRS(O)₂—NR-aryl,—NRS(O)₂—NR-substituted aryl, —NRS(O)₂—NR-heteroaryl,—NRS(O)₂—NR-substituted heteroaryl, —NRS(O)₂—NR-heterocyclic,—NRS(O)₂—NR-substituted heterocyclic where R is hydrogen or alkyl, mono-and di-alkylamino, mono- and di-(substituted alkyl)amino, mono- anddi-arylamino, mono- and di-substituted arylamino, mono- anddi-heteroarylamino, mono- and di-substituted heteroarylamino, mono- anddi-heterocyclic amino, mono- and di-substituted heterocyclic amino,unsymmetric di-substituted amines having different substituents selectedfrom alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl,substituted heteroaryl, heterocyclic and substituted heterocyclic andamino groups on the substituted aryl blocked by conventional blockinggroups such as Boc, Cbz, formyl, and the like or substituted with—SO₂NRR where R is hydrogen or alkyl.

“Aryloxy” refers to the group aryl-O- which includes, by way of example,phenoxy, naphthoxy, and the like.

“Substituted aryloxy” refers to substituted aryl-O-groups.

“Aryloxyaryl” refers to the group -aryl-O-aryl.

“Substituted aryloxyaryl” refers to aryloxyaryl groups substituted withfrom 1 to 3 substituents on either or both aryl rings selected from thegroup consisting of hydroxy, acyl, acylamino, thiocarbonylamino,acyloxy, alkyl, substituted alkyl, alkoxy, substituted alkoxy, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, amidino,alkylamidino, thioamidino, amino, aminoacyl, aminocarbonyloxy,aminocarbonylamino, aminothiocarbonylamino, aryl, substituted aryl,aryloxy, substituted aryloxy, cycloalkoxy, substituted cycloalkoxy,heteroaryloxy, substituted heteroaryloxy, heterocyclyloxy, substitutedheterocyclyloxy, carboxyl, carboxylalkyl, carboxyl-substituted alkyl,carboxyl-cycloalkyl, carboxyl-substituted cycloalkyl, carboxylaryl,carboxyl-substituted aryl, carboxylheteroaryl, carboxyl-substitutedheteroaryl, carboxylheterocyclic, carboxyl-substituted heterocyclic,carboxylamido, cyano, thiol, thioalkyl, substituted thioalkyl, thioaryl,substituted thioaryl, thioheteroaryl, substituted thioheteroaryl,thiocycloalkyl, substituted thiocycloalkyl, thioheterocyclic,substituted thioheterocyclic, cycloalkyl, substituted cycloalkyl,guanidino, guanidinosulfone, halo, nitro, heteroaryl, substitutedheteroaryl, heterocyclic, substituted heterocyclic, cycloalkoxy,substituted cycloalkoxy, heteroaryloxy, substituted heteroaryloxy,heterocyclyloxy, substituted heterocyclyloxy, oxycarbonylamino,oxythiocarbonylamino, —S(O)₂-alkyl, —S(O)₂-substituted alkyl,—S(O)₂-cycloalkyl, —S(O)₂-substituted cycloalkyl, —S(O)₂-alkenyl,—S(O)₂-substituted alkenyl, —S(O)₂-aryl, —S(O)₂-substituted aryl,—S(O)₂-heteroaryl, —S(O)₂-substituted heteroaryl, —S(O)₂-heterocyclic,—S(O)₂-substituted heterocyclic, —OS(O)₂-alkyl, —OS(O)₂-substitutedalkyl, —OS(O)₂-aryl, —OS(O)₂-substituted aryl, —OS(O)₂-heteroaryl,—OS(O)₂-substituted heteroaryl, —OS(O)₂-heterocyclic,—OS(O)₂-substituted heterocyclic, —OSO₂—NRR where R is hydrogen oralkyl, —NRS(O)₂-alkyl, —NRS(O)₂-substituted alkyl, —NRS(O)₂-aryl,—NRS(O)₂-substituted aryl, —NRS(O)₂-heteroaryl, —NRS(O)₂-substitutedheteroaryl, —NRS(O)₂-heterocyclic, —NRS(O)₂-substituted heterocyclic,—NRS(O)₂—NR-alkyl, —NRS(O)₂—NR-substituted alkyl, —NRS(O)₂—NR-aryl,—NRS(O)₂—NR-substituted aryl, —NRS(O)₂—NR-heteroaryl,—NRS(O)₂—NR-substituted heteroaryl, —NRS(O)₂—NR-heterocyclic,—NRS(O)₂—NR-substituted heterocyclic where R is hydrogen or alkyl, mono-and di-alkylamino, mono- and di-(substituted alkyl)amino, mono- anddi-arylamino, mono- and di-substituted arylamino, mono- anddi-heteroarylamino, mono- and di-substituted heteroarylamino, mono- anddi-heterocyclic amino, mono- and di-substituted heterocyclic amino,unsymmetric di-substituted amines having different substituents selectedfrom alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl,substituted heteroaryl, heterocyclic and substituted heterocyclic andamino groups on the substituted aryl blocked by conventional blockinggroups such as Boc, Cbz, formyl, and the like or substituted with—SO₂NRR where R is hydrogen or alkyl.

“4-Benzyl-5-oxo-4-azatricyclo[4.2.1.0(3,7)]nonane-3-carboxylic acid”refers to a compound of the formula:

“Cycloalkyl” refers to cyclic alkyl groups of from 3 to 8 carbon atomshaving a single cyclic ring including, by way of example, cyclopropyl,cyclobutyl, cyclopentyl, cyclooctyl and the like. Excluded from thisdefinition are multi-ring or fused-ring alkyl groups such asadamantanyl, and the like.

“Cycloalkenyl” refers to cyclic alkenyl groups of from 3 to 8 carbonatoms having single or multiple unsaturation but which are not aromatic.

“Substituted cycloalkyl” and “substituted cycloalkenyl” refer to acycloalkyl and cycloalkenyl groups, preferably of from 3 to 8 carbonatoms, having from 1 to 5 substituents selected from the groupconsisting of oxo (═O), thioxo (═S), alkoxy, substituted alkoxy, acyl,acylamino, thiocarbonylamino, acyloxy, amino, amidino, alkylamidino,thioamidino, aminoacyl, aminocarbonylamino, aminothiocarbonylamino,aminocarbonyloxy, aryl, substituted aryl, aryloxy, substituted aryloxy,aryloxyaryl, substituted aryloxyaryl, halogen, hydroxyl, cyano, nitro,carboxyl, carboxylalkyl, carboxyl-substituted alkyl,carboxyl-cycloalkyl, carboxyl-substituted cycloalkyl, carboxylaryl,carboxyl-substituted aryl, carboxylheteroaryl, carboxyl-substitutedheteroaryl, carboxylheterocyclic, carboxyl-substituted heterocyclic,cycloalkyl, substituted cycloalkyl, guanidino, guanidinosulfone, thiol,thioalkyl, substituted thioalkyl, thioaryl, substituted thioaryl,thiocycloalkyl, substituted thiocycloalkyl, thioheteroaryl, substitutedthioheteroaryl, thioheterocyclic, substituted thioheterocyclic,heteroaryl, substituted heteroaryl, heterocyclic, substitutedheterocyclic, cycloalkoxy, substituted cycloalkoxy, heteroaryloxy,substituted heteroaryloxy, heterocyclyloxy, substituted heterocyclyloxy,oxycarbonylamino, oxythiocarbonylamino, —OS(O)₂-alkyl,—OS(O)₂-substituted alkyl, —OS(O)₂-aryl, —OS(O)₂-substituted aryl,—OS(O)₂-heteroaryl, —OS(O)₂-substituted heteroaryl,—OS(O)₂-heterocyclic, —OS(O)₂-substituted heterocyclic, —OSO₂—NRR whereR is hydrogen or alkyl, —NRS(O)₂-alkyl, —NRS(O)₂-substituted alkyl,—NRS(O)₂-aryl, —NRS(O)₂-substituted aryl, —NRS(O)₂-heteroaryl,—NRS(O)₂-substituted heteroaryl, —NRS(O)₂-heterocyclic,—NRS(O)₂-substituted heterocyclic, —NRS(O)₂—NR-alkyl,—NRS(O)₂—NR-substituted alkyl, —NRS(O)₂—NR-aryl, —NRS(O)₂—NR-substitutedaryl, —NRS(O)₂—NR-heteroaryl, —NRS(O)₂—NR-substituted heteroaryl,—NRS(O)₂—NR-heterocyclic, —NRS(O)₂—NR-substituted heterocyclic where Ris hydrogen or alkyl, mono- and di-alkylamino, mono- and di-(substitutedalkyl)amino, mono- and di-arylamino, mono- and di-substituted arylamino,mono- and di-heteroarylamino, mono- and di-substituted heteroarylamino,mono- and di-heterocyclic amino, mono- and di-substituted heterocyclicamino, unsymmetric di-substituted amines having different substituentsselected from alkyl, substituted alkyl, aryl, substituted aryl,heteroaryl, substituted heteroaryl, heterocyclic and substitutedheterocyclic and substituted alkynyl groups having amino groups blockedby conventional blocking groups such as Boc, Cbz, formyl, and the likeor alkynyl/substituted alkynyl groups substituted with —SO₂-alkyl,—SO₂-substituted alkyl, —SO₂-alkenyl, —SO₂-substituted alkenyl,—SO₂-cycloalkyl, —SO₂-substituted cycloalkyl, —SO₂-aryl,—SO₂-substituted aryl, —SO₂-heteroaryl, —SO₂-substituted heteroaryl,—SO₂-heterocyclic, —SO₂-substituted heterocyclic and —SO₂NRR where R ishydrogen or alkyl.

“Cycloalkoxy” refers to O-cycloalkyl groups.

“Substituted cycloalkoxy” refers to O-substituted cycloalkyl groups.

“Guanidino” refers to the groups —NRC(═NR)NRR, —NRC(═NR)NR-alkyl,—NRC(═NR)NR-substituted alkyl, —NRC(═NR)NR-alkenyl,—NRC(═NR)NR-substituted alkenyl, —NRC(═NR)NR-alkynyl,—NRC(═NR)NR-substituted alkynyl, —NRC(═NR)NR-aryl,—NRC(═NR)NR-substituted aryl, —NRC(═NR)NR-cycloalkyl,—NRC(═NR)NR-heteroaryl, —NRC(═NR)NR-substituted heteroaryl,—NRC(═NR)NR-heterocyclic, and —NRC(═NR)NR-substituted heterocyclic whereeach R is independently hydrogen and alkyl as well as where one of theamino groups is blocked by conventional blocking groups such as Boc,Cbz, formyl, and the like and wherein alkyl, substituted alkyl, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, aryl, substituted aryl, heteroaryl, substitutedheteroaryl, heterocyclic and substituted heterocyclic are as definedherein.

“Guanidinosulfone” refers to the groups —NRC(═NR)NRSO₂-alkyl,—NRC(═NR)NRSO₂-substituted alkyl, —NRC(═NR)NRSO₂-alkenyl,—NRC(═NR)NRSO₂-substituted alkenyl, —NRC(═NR)NRSO₂-alkynyl,—NRC(═NR)NRSO₂-substituted alkynyl, —NRC(═NR)NRSO₂-aryl,—NRC(═NR)NRSO₂-substituted aryl, —NRC(═NR)NRSO₂-cycloalkyl,—NRC(═NR)NRSO₂-substituted cycloalkyl, —NRC(═NR)NRSO₂-heteroaryl, and—NRC(═NR)NRSO₂-substituted heteroaryl, —NRC(═NR)NRSO₂-heterocyclic, and—NRC(═NR)NRSO₂-substituted heterocyclic where each R is independentlyhydrogen and alkyl and wherein alkyl, substituted alkyl, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, cycloalkyl,substituted cycloalkyl, aryl, substituted aryl, heteroaryl, substitutedheteroaryl, heterocyclic and substituted heterocyclic are as definedherein.

“Halo” or “halogen” refers to fluoro, chloro, bromo and iodo andpreferably is either chloro or bromo.

“Heteroalkylene” refers to an alkylene group in which from 1 to 5,preferable from 1 to 3, of the carbon atoms in the alkylene chain havebeen replaced with a hetereoatom selected from nitrogen, oxygen orsulfur. By way of illustration, the term heteroalkylene includes—CH₂—O—CH₂—, —CH₂—S—CH₂—, —NHCH₂— and the like.

“Substituted heteroalkylene” refers to a heteroalkylene group havingfrom 1 to 5 substituents selected from the group consisting of alkoxy,substituted alkoxy, acyl, acylamino, thiocarbonylamino, acyloxy, amino,amidino, alkyl amidino, thioamidino, aminoacyl, aminocarbonylamino,aminothiocarbonylamino, aminocarbonyloxy, aryl, substituted aryl,aryloxy, substituted aryloxy, aryloxylaryl, substituted aryloxyaryl,cyano, halogen, hydroxyl, nitro, carboxyl, carboxylalkyl,carboxyl-substituted alkyl, carboxyl-cycloalkyl, carboxyl-substitutedcycloalkyl, carboxylaryl, carboxyl-substituted aryl, carboxylheteroaryl,carboxyl-substituted heteroaryl, carboxylheterocyclic,carboxyl-substituted heterocyclic, cycloalkyl, substituted cycloalkyl,guanidino, guanidinosulfone, thiol, thioalkyl, substituted thioalkyl,thioaryl, substituted thioaryl, thiocycloalkyl, substitutedthiocycloalkyl, thioheteroaryl, substituted thioheteroaryl,thioheterocyclic, substituted thioheterocyclic, heteroaryl, substitutedaryl, substituted heteroaryl, heterocyclic, substituted heterocyclic,cycloalkoxy, substituted cycloalkoxy, heteroaryloxy, substitutedheteroaryloxy, heterocyclyloxy, substituted heterocyclyloxy,oxycarbonylamino, oxythiocarbonylamino, —OS(O)₂-alkyl,—OS(O)₂-substituted alkyl, —OS(O)₂-aryl, —OS(O)₂-substituted aryl,—OS(O)₂-heteroaryl, —OS(O)₂-substituted heteroaryl,—OS(O)₂-heterocyclic, —OS(O)₂-substituted heterocyclic, —OSO₂— NRR whereR is hydrogen or alkyl, —NRS(O)₂-alkyl, —NRS(O)₂-substituted alkyl,—NRS(O)₂-aryl, —NRS(O)₂-substituted aryl, —NRS(O)₂-heteroaryl,-NRS(O)₂-substituted heteroaryl, —NRS(O)₂-heterocyclic,—NRS(O)₂-substituted heterocyclic, —NRS(O)₂—NR-alkyl,—NRS(O)₂—NR-substituted alkyl, —NRS(O)₂—NR-aryl, —NRS(O)₂—NR-substitutedaryl, —NRS(O)₂—NR-heteroaryl, —NRS(O)₂—NR-substituted heteroaryl,—NRS(O)₂—NR-heterocyclic, —NRS(O)₂—NR-substituted heterocyclic where Ris hydrogen or alkyl, mono- and di-alkylamino, mono- and di-(substitutedalkyl)amino, mono- and di-arylamino, mono- and di-substituted arylamino,mono- and di-heteroarylamino, mono- and di-substituted heteroarylamino,mono- and di-heterocyclic amino, mono- and di-substituted heterocyclicamino, unsymmetric di-substituted amines having different substituentsselected from alkyl, substituted alkyl, aryl, substituted aryl,heteroaryl, substituted heteroaryl, heterocyclic and substitutedheterocyclic and substituted alkyl groups having amino groups blocked byconventional blocking groups such as Boc, Cbz, formyl, and the like oralkyl/substituted alkyl groups substituted with —SO₂-alkyl,—SO₂-substituted alkyl, —SO₂-alkenyl, —SO₂-substituted alkenyl,—SO₂-cycloalkyl, —SO₂-substituted cycloalkyl, —SO₂-aryl,—SO₂-substituted aryl, —SO₂-heteroaryl, —SO₂-substituted heteroaryl,—SO₂-heterocyclic, —SO₂-substituted heterocyclic and —SO₂NRR where R ishydrogen or alkyl.

“Heteroaryl” refers to an aromatic carbocyclic group of from 2 to 10carbon atoms and 1 to 4 heteroatoms selected from oxygen, nitrogen andsulfur within the ring. Such heteroaryl groups can have a single ring(e.g., pyridyl or furyl) or multiple condensed rings (e.g., indolizinylor benzothienyl). Preferred heteroaryls include pyridyl, pyrrolyl,indolyl and furyl.

“Substituted heteroaryl” refers to heteroaryl groups which aresubstituted with from 1 to 3 substituents selected from the groupconsisting of hydroxy, acyl, acylamino, thiocarbonylamino, acyloxy,alkyl, substituted alkyl, alkoxy, substituted alkoxy, alkenyl,substituted alkenyl, alkynyl, substituted alkynyl, amidino,alkylamidino, thioamidino, amino, aminoacyl, aminocarbonyloxy,aminocarbonylamino, aminothiocarbonylamino, aryl, substituted aryl,aryloxy, substituted aryloxy, cycloalkoxy, substituted cycloalkoxy,heteroaryloxy, substituted heteroaryloxy, heterocyclyloxy, substitutedheterocyclyloxy, carboxyl, carboxylalkyl, carboxyl-substituted alkyl,carboxyl-cycloalkyl, carboxyl-substituted cycloalkyl, carboxylaryl,carboxyl-substituted aryl, carboxylheteroaryl, carboxyl-substitutedheteroaryl, carboxylheterocyclic, carboxyl-substituted heterocyclic,carboxylamido, cyano, thiol, thioalkyl, substituted thioalkyl, thioaryl,substituted thioaryl, thioheteroaryl, substituted thioheteroaryl,thiocycloalkyl, substituted thiocycloalkyl, thioheterocyclic,substituted thioheterocyclic, cycloalkyl, substituted cycloalkyl,guanidino, guanidinosulfone, halo, nitro, heteroaryl, substitutedheteroaryl, heterocyclic, substituted heterocyclic, cycloalkoxy,substituted cycloalkoxy, heteroaryloxy, substituted heteroaryloxy,heterocyclyloxy, substituted heterocyclyloxy, oxycarbonylamino,oxythiocarbonylamino, —S(O)₂-alkyl, —S(O)₂-substituted alkyl,—S(O)₂-cycloalkyl, —S(O)₂-substituted cycloalkyl, —S(O)₂-alkenyl,—S(O)₂-substituted alkenyl, —S(O)₂-aryl, —S(O)₂-substituted aryl,—S(O)₂-heteroaryl, —S(O)₂-substituted heteroaryl, —S(O)₂-heterocyclic,—S(O)₂-substituted heterocyclic, —OS(O)₂-alkyl, —OS(O)₂-substitutedalkyl, —OS(O)₂-aryl, —OS(O)₂-substituted aryl, —OS(O)₂-heteroaryl,—OS(O)₂-substituted heteroaryl, —OS(O)₂-heterocyclic,—OS(O)₂-substituted heterocyclic, —OSO₂—NRR where R is hydrogen oralkyl, —NRS(O)₂-alkyl, —NRS(O)₂-substituted alkyl, —NRS(O)₂-aryl,—NRS(O)₂-substituted aryl, —NRS(O)₂-heteroaryl, —NRS(O)₂-substitutedheteroaryl, —NRS(O)₂-heterocyclic, —NRS(O)₂-substituted heterocyclic,—NRS(O)₂—NR-alkyl, —NRS(O)₂—NR-substituted alkyl, —NRS(O)₂—NR-aryl,—NRS(O)₂—NR-substituted aryl, —NRS(O)₂—NR-heteroaryl,—NRS(O)₂—NR-substituted heteroaryl, —NRS(O)₂—NR-heterocyclic,—NRS(O)₂—NR-substituted heterocyclic where R is hydrogen or alkyl, mono-and di-alkylamino, mono- and di-(substituted alkyl)amino, mono- anddi-arylamino, mono- and di-substituted arylamino, mono- anddi-heteroarylamino, mono- and di-substituted heteroarylamino, mono- anddi-heterocyclic amino, mono- and di-substituted heterocyclic amino,unsymmetric di-substituted amines having different substituents selectedfrom alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl,substituted heteroaryl, heterocyclic and substituted heterocyclic andamino groups on the substituted aryl blocked by conventional blockinggroups such as Boc, Cbz, formyl, and the like or substituted with—SO₂NRR where R is hydrogen or alkyl.

“Heteroaryloxy” refers to the group —O-heteroaryl and “substitutedheteroaryloxy” refers to the group —O-substituted heteroaryl.

“Heterocycle” or “heterocyclic” refers to a saturated or unsaturatedgroup having a single ring or multiple condensed rings, from 1 to 10carbon atoms and from 1 to 4 hetero atoms selected from nitrogen, sulfuror oxygen within the ring wherein, in fused ring systems, one or more ofthe rings can be aryl or heteroaryl.

“Substituted heterocyclic” refers to heterocycle groups which aresubstituted with from 1 to 3 substituents selected from the groupconsisting of oxo (═O), thioxo (═S), alkoxy, substituted alkoxy, acyl,acylamino, thiocarbonylamino, acyloxy, amino, amidino, alkylamidino,thioamidino, aminoacyl, aminocarbonylamino, aminothiocarbonylamino,aminocarbonyloxy, aryl, substituted aryl, aryloxy, substituted aryloxy,aryloxyaryl, substituted aryloxyaryl, halogen, hydroxyl, cyano, nitro,carboxyl, carboxylalkyl, carboxyl-substituted alkyl,carboxyl-cycloalkyl, carboxyl-substituted cycloalkyl, carboxylaryl,carboxyl-substituted aryl, carboxylheteroaryl, carboxyl-substitutedheteroaryl, carboxylheterocyclic, carboxyl-substituted heterocyclic,cycloalkyl, substituted cycloalkyl, guanidino, guanidinosulfone, thiol,thioalkyl, substituted thioalkyl, thioaryl, substituted thioaryl,thiocycloalkyl, substituted thiocycloalkyl, thioheteroaryl, substitutedthioheteroaryl, thioheterocyclic, substituted thioheterocyclic,heteroaryl, substituted heteroaryl, heterocyclic, substitutedheterocyclic, cycloalkoxy, substituted cycloalkoxy, heteroaryloxy,substituted heteroaryloxy, heterocyclyloxy, substituted heterocyclyloxy,oxycarbonylamino, oxythiocarbonylamino, —OS(O)₂-alkyl,—OS(O)₂-substituted alkyl, —OS(O)₂-aryl, —OS(O)₂-substituted aryl,—OS(O)₂-heteroaryl, —OS(O)₂-substituted heteroaryl,—OS(O)₂-heterocyclic, —OS(O)₂-substituted heterocyclic, —OSO₂—NRR whereR is hydrogen or alkyl, —NRS(O)₂-alkyl, —NRS(O)₂-substituted alkyl,—NRS(O)₂-aryl, —NRS(O)₂-substituted aryl, —NRS(O)₂-heteroaryl,—NRS(O)₂-substituted heteroaryl, —NRS(O)₂-heterocyclic,—NRS(O)₂-substituted heterocyclic, —NRS(O)₂—NR-alkyl,—NRS(O)₂—NR-substituted alkyl, —NRS(O)₂—NR-aryl, —NRS(O)₂—NR-substitutedaryl, —NRS(O)₂—NR-heteroaryl, —NRS(O)₂—NR-substituted heteroaryl,—NRS(O)₂—NR-heterocyclic, —NRS(O)₂—NR-substituted heterocyclic where Ris hydrogen or alkyl, mono- and di-alkylamino, mono- and di-(substitutedalkyl)amino, mono- and di-arylamino, mono- and di-substituted arylamino,mono- and di-heteroarylamino, mono- and di-substituted heteroarylamino,mono- and di-heterocyclic amino, mono- and di-substituted heterocyclicamino, unsymmetric di-substituted amines having different substituentsselected from alkyl, substituted alkyl, aryl, substituted aryl,heteroaryl, substituted heteroaryl, heterocyclic and substitutedheterocyclic and substituted alkynyl groups having amino groups blockedby conventional blocking groups such as Boc, Cbz, formyl, and the likeor alkynyl/substituted alkynyl groups substituted with —SO₂-alkyl,—SO₂-substituted alkyl, —SO₂-alkenyl, —SO₂-substituted alkenyl,—SO₂-cycloalkyl, —SO₂-substituted cycloalkyl, —SO₂-aryl,—SO₂-substituted aryl, —SO₂-heteroaryl, —SO₂-substituted heteroaryl,—SO₂-heterocyclic, —SO₂-substituted heterocyclic and —SO₂NRR where R ishydrogen or alkyl.

Examples of heterocycles and heteroaryls include, but are not limitedto, azetidine, pyrrole, imidazole, pyrazole, pyridine, pyrazine,pyrimidine, pyridazine, indolizine, isoindole, indole, dihydroindole,indazole, purine, quinolizine, isoquinoline, quinoline, phthalazine,naphthylpyridine, quinoxaline, quinazoline, cinnoline, pteridine,carbazole, carboline, phenanthridine, acridine, phenanthroline,isothiazole, phenazine, isoxazole, phenoxazine, phenothiazine,imidazolidine, imidazoline, piperidine, piperazine, indoline,phthalimide, 1,2,3,4-tetrahydroisoquinoline,4,5,6,7-tetrahydrobenzo[b]thiophene, thiazole, thiazolidine, thiophene,benzo[b]thiophene, morpholino, thiomorpholino, piperidinyl, pyrrolidine,tetrahydrofuranyl, and the like.

“Heterocyclyloxy” refers to the group —O-heterocyclic and “substitutedheterocyclyloxy” refers to the group —O-substituted heterocyclic.

“L-Pyroglutamic acid” refers to (S)-(−)-2-pyrrolidone-5-carboxylic acid.

“Thiol” refers to the group —SH.

“Thioalkyl” refers to the groups —S-alkyl

“Substituted thioalkyl” refers to the group —S-substituted alkyl.

“Thiocycloalkyl” refers to the groups —S-cycloalkyl.

“Substituted thiocycloalkyl” refers to the group —S-substitutedcycloalkyl.

“Thioaryl” refers to the group —S-aryl and “substituted thioaryl” refersto the group —S-substituted aryl.

“Thioheteroaryl” refers to the group —S-heteroaryl and “substitutedthioheteroaryl” refers to the group —S-substituted heteroaryl.

“Thioheterocyclic” refers to the group —S-heterocyclic and “substitutedthioheterocyclic” refers to the group —S-substituted heterocyclic.

“Pharmaceutically acceptable salt” refers to pharmaceutically acceptablesalts of a compound of Formula I which salts are derived from a varietyof organic and inorganic counter ions well known in the art and include,by way of example only, sodium, potassium, calcium, magnesium, ammonium,tetraalkylammonium, and the like; and when the molecule contains a basicfunctionality, salts of organic or inorganic acids, such ashydrochloride, hydrobromide, tartrate, mesylate, acetate, maleate,oxalate and the like.

Compound Preparation

The compounds of this invention can be prepared from readily availablestarting materials using the following general methods and procedures.It will be appreciated that where typical or preferred processconditions (i.e., reaction temperatures, times, mole ratios ofreactants, solvents, pressures, etc.) are given, other processconditions can also be used unless otherwise stated. Optimum reactionconditions may vary with the particular reactants or solvent used, butsuch conditions can be determined by one skilled in the art by routineoptimization procedures.

Additionally, as will be apparent to those skilled in the art,conventional protecting groups may be necessary to prevent certainfunctional groups from undergoing undesired reactions. Suitableprotecting groups for various functional groups as well as suitableconditions for protecting and deprotecting particular functional groupsare well known in the art. For example, numerous protecting groups aredescribed in T. W. Greene and G. M. Wuts, Protecting Groups in OrganicSynthesis, Second Edition, Wiley, N.Y., 1991, and references citedtherein.

Furthermore, the compounds of this invention will typically contain oneor more chiral centers. Accordingly, if desired, such compounds can beprepared or isolated as pure stereoisomers, i.e., as individualenantiomers or diastereomers, or as stereoisomer-enriched mixtures. Allsuch stereoisomers (and enriched mixtures) are included within the scopeof this invention, unless otherwise indicated. Pure stereoisomers (orenriched mixtures) may be prepared using, for example, optically activestarting materials or stereoselective reagents well-known in the art.Alternatively, racemic mixtures of such compounds can be separatedusing, for example, chiral column chromatography, chiral resolvingagents and the like.

In a preferred method of synthesis, the compounds of formula I and IAare prepared by first alkylating a cyclic compound of formula II:

wherein R′ is alkyl, such as methyl, ethyl and the like, and R² and R³are as defined herein, with a suitable alkylating agent to provide anN-alkylated compound of formula III:

wherein R′ and R¹-R³ are as defined herein.

This reaction is typically conducted by contacting the cyclic compoundof formula II with at least one equivalent of a strong base, such aspotassium tert-butoxide, in the presence of at least one equivalent ofthe alkylating agent. Generally, the reaction is conducted in an inertdiluent, such as THF and the like, at a temperature ranging from about0° C. to about 40° C. for about 1 to about 24 hours. Upon completion ofthe reaction, the resulting N-alkylated compound III is recovered byconventional methods including neutralization, extraction,precipitation, chromatography, filtration, and the like.

The cyclic compounds of formula II employed in the above reaction areeither known compounds or compounds that can be prepared from knowncompounds by conventional synthetic procedures. Examples of suitablecompounds for use in this reaction include, but are not limited to,L-pyroglutamic acid esters, D-pyroglutamic acid esters, D,L-pyroglutamicacid esters, 3-oxomorpholine-5-carboxylic acid esters,3-oxothiomorpholine-5-carboxylic acid esters,5-oxo-4-azatricyclo[4.2.1.0(3,7]nonane-3-carboxylic acid esters and thelike.

Any suitable alkylating agent may be employed in this reaction.Preferred alkylating agents included benzyl halides, such as benzylbromide and benzyl chlorides. Particularly preferred alkylating agentsinclude benzyl bromide, 3-chlorobenzyl bromide, 4-chlorobenzyl bromide,3,4-dichlorobenzyl bromide, 4-methylbenzyl bromide, 4-methoxybenzylbromide, 4-fluorobenzyl bromide, 4-cyanobenzyl bromide, 4-nitrobenzylbromide and the like.

After completion of the alkylation reaction, subsequent hydrolysis ofthe ester group using conventional reagents and conditions, i.e.,treatment with an alkali metal hydroxide in an inert diluent such asmethanol/water, then affords the corresponding carboxylic acid offormula IV:

wherein R¹-R³ are as defined herein.

Alternatively, intermediate IV can be prepared by reductive alkylationof an amino dicarboxylic acid derivative of formula IVa:

where R² and R³ are as defined herein, with an aldehyde of the formula:R¹—CHO, where R¹ is as defined herein, using conventional reductivealkylation conditions and reagents, followed by cyclization of theresulting N-alkylated intermediate. The reductive alkylation reaction istypically conducted by contacting the amino compound IVa with at leastone equivalent, preferably about 1.1 to about 1.5 equivalents, of analdehyde and at least one equivalent based on the amino compound of ametal hydride reducing agent, such as sodium cyanoborohydride, in aninert diluent, such as methanol, tetrahydrofuran, mixtures thereof andthe like, at a temperature ranging from about 0° C. to about 50° C. forabout 1 to about 72 hours. The resulting N-alkylated intermediate isthen cyclized by acidification and heating to afford intermediate IV.This reaction typically affords products of high optical purity when anoptically active amino dicarboxylic acid, such as L-glutamic acid, isemployed.

The compounds of formula I are then prepared by coupling theintermediate of formula IV with an amino acid derivative of formula V:

wherein R⁴ and R⁵ are as defined herein.

This coupling reaction is typically conducted using well-known couplingreagents such as carbodiimides, BOP reagent(benzotriazol-1-yloxy-tris(dimethylamino)phosphoniumhexafluorophosphonate) and the like. Suitable carbodiimides include, byway of example, dicyclohexylcarbodiimide (DCC),1-(3-dimethylaminopropyl)-3-ethylcarbodiimide (EDC) and the like. Ifdesired, polymer supported forms of carbodiimide coupling reagents mayalso be used including, for example, those described in TetrahedronLetters, 34(48), 7685 (1993). Additionally, well-known couplingpromoters, such as N-hydroxysuccinimide, 1-hydroxybenzotriazole and thelike, may be used to facilitate the coupling reaction.

This coupling reaction is typically conducted by contacting intermediateIV with about 1 to about 2 equivalents of the coupling reagent and atleast one equivalent, preferably about 1 to about 1.2 equivalents, ofamino acid derivative V in an inert diluent, such as dichloromethane,chloroform, acetonitrile, tetrahydrofuran, N,N-dimethylformamide and thelike. Generally, this reaction is conducted at a temperature rangingfrom about 0° C. to about 37° C. for about 12 to about 24 hours. Uponcompletion of the reaction, the compound of formula IA is recovered byconventional methods including neutralization, extraction,precipitation, chromatography, filtration, and the like.

Alternatively, the intermediate IV can be converted into an acid halideand the acid halide coupled with amino acid derivative V to providecompounds of formula IA. The acid halide of IV can be prepared bycontacting IV with an inorganic acid halide, such as thionyl chloride,phosphorous trichloride, phosphorous tribromide or phosphorouspentachloride, or preferably, with oxalyl chloride under conventionalconditions. Generally, this reaction is conducted using about 1 to 5molar equivalents of the inorganic acid halide or oxalyl chloride,either neat or in an inert solvent, such as dichloromethane or carbontetrachloride, at temperature in the range of about 0° C. to about 80°C. for about 1 to about 48 hours. A catalyst, such asN,N-dimethylformamide, may also be used in this reaction.

The acid halide of intermediate IV is then contacted with at least oneequivalent, preferably about 1.1 to about 1.5 equivalents, of amino acidderivative V in an inert diluent, such as dichloromethane, at atemperature ranging from about −70° C. to about 40° C. for about 1 toabout 24 hours. Preferably, this reaction is conducted in the presenceof a suitable base to scavenge the acid generated during the reaction.Suitable bases include, by way of example, tertiary amines, such astriethylamine, diisopropylethylamine, N-methylmorpholine and the like.Alternatively, the reaction can be conducted under Schotten-Baumann-typeconditions using aqueous alkali, such as sodium hydroxide and the like.Upon completion of the reaction, the compound of formula IA is recoveredby conventional methods including neutralization, extraction,precipitation, chromatography, filtration, and the like.

The amino acid derivatives of formula V employed in the above reactionsare either known compounds or compounds that can be prepared from knowncompounds by conventional synthetic procedures. For example, amino acidderivatives of formula V can be prepared by C-alkylating commerciallyavailable diethyl 2-acetamidomalonate (Aldrich, Milwaukee, Wis., USA)with an alkyl or substituted alkyl halide. This reaction is typicallyconducted by treating the diethyl 2-acetamidomalonate with at least oneequivalent of sodium ethoxide and at least one equivalent of an alkyl orsubstituted alkyl halide in refluxing ethanol for about 6 to about 12hours. The resulting C-alkylated malonate is then deacetylated,hydrolyzed and decarboxylated by heating in aqueous hydrochloric acid atreflux for about 6 to about 12 hours to provide the amino acid,typically as the hydrochloride salt.

Examples of amino acid derivatives of formula V suitable for use in theabove reactions include, but are not limited to, L-alanine methyl ester,L-isoleucine methyl ester, L-leucine methyl ester, L-valine methylester, β-tert-butyl-L-aspartic acid methyl ester, L-asparaginetert-butyl ester, ε-Boc-L-lysine methyl ester, ε-Cbz-L-lysine methylester, γ-tert-butyl-L-glutamic acid methyl ester, L-glutamine tert-butylester, L-(N-methyl)histidine methyl ester, L-(N-benzyl)histidine methylester, L-methionine methyl ester, L-(O-benzyl)serine methyl ester,L-tryptophan methyl ester, L-phenylalanine methyl ester, L-phenylalanineisopropyl ester, L-phenylalanine benzyl ester, L-phenylalaninamide,N-methyl-L-phenylalanine benzyl ester, 3-carboxy-D,L-phenylalaninemethyl ester, 4-carboxy-D,L-phenylalanine methyl ester,L4-chlorophenylalanine methyl ester,L-4-(3-dimethylaminopropyloxy)phenylalanine methyl ester,L4-iodophenylalanine methyl ester, L-3,4-methylenedioxyphenylalaninemethyl ester, L-3,4-ethylenedioxyphenylalanine methyl ester,L-4-nitrophenylalanine methyl ester, L-tyrosine methyl ester,D,L-homophenylalanine methyl ester, L-(O-methyl)tyrosine methyl ester,L-(O-tert-butyl)tyrosine methyl ester, L-(O-benzyl)tyrosine methylester, L-3,5-diiodotyrosine methyl ester, L-3-iodotyrosine methyl ester,β-(1-naphthyl)-L-alanine methyl ester, β-(2-naphthyl)-L-alanine methylester, β-(2-thienyl)-L-alanine methyl ester, β-cyclohexyl-L-alaninemethyl ester, β-(2-pyridyl)-L-alanine methyl ester,β-(3-pyridyl)-L-alanine methyl ester, β-(4-pyridyl)-L-alanine methylester, β-(2-thiazolyl)-D,L-alanine methyl ester,β-(1,2,4-triazol-3-yl)-D,L-alanine methyl ester, and the like. Ifdesired, of course, other esters or amides of the above-describedcompounds may also be employed.

For ease of synthesis, the compounds of formula I are typically preparedas an ester, i.e., where R⁵ is an alkoxy or substituted alkoxy group andthe like. If desired, the ester group can be hydrolysed usingconventional conditions and reagents to provide the correspondingcarboxylic acid. Typically, this reaction is conducted by treating theester with at least one equivalent of an alkali metal hydroxide, such aslithium, sodium or potassium hydroxide, in an inert diluent, such asmethanol or mixtures of methanol and water, at a temperature rangingabout 0° C. to about 24° C. for about 1 to about 12 hours.Alternatively, benzyl esters may be removed by hydrogenolysis using apalladium catalyst, such as palladium on carbon, or tert-butyl esterscan be hydrolyzed by exposure to strong acids, such as formic acid ortrifluoroacetic acid. The resulting carboxylic acids may be coupled, ifdesired, to amines such as β-alanine ethyl ester, hydroxyamines such ashydroxylamine and N-hydroxysuccinimide, alkoxyamines and substitutedalkoxyamines such as O-methylhydroxylamine and O-benzylhydroxylamine,and the like, using conventional coupling reagents and conditions asdescribed above.

As will be apparent to those skilled in the art, other functional groupspresent on any of the substituents of the compounds of formula I can bereadily modified or derivatized either before or after theabove-described coupling reactions using well-known syntheticprocedures. For example, a nitro group present on a substituent of acompound of formula I or an intermediate thereof may be readily reducedby hydrogenation in the presence of a palladium catalyst, such aspalladium on carbon, to provide the corresponding amino group. Thisreaction is typically conducted at a temperature of from about 20° C. toabout 50° C. for about 6 to about 24 hours in an inert diluent, such asmethanol. Compounds having a nitro group on the R⁴ substituent can beprepared, for example, by using a 4-nitrophenylalanine derivative andthe like in the above-described coupling reactions.

Similarly, a pyridyl group can be hydrogenated in the presence of aplatinum catalyst, such as platinum oxide, in an acidic diluent toprovide the corresponding piperidinyl analogue. Generally, this reactionis conducted by treating the pyridine compound with hydrogen at apressure ranging from about 20 psi to about 60 psi, preferably about 40psi, in the presence of the catalyst at a temperature of about 20° C. toabout 50° C. for about 2 to about 24 hours in an acidic diluent, such asa mixture of methanol and aqueous hydrochloric acid. Compounds having apyridyl group can be readily prepared by using, for example,β-(2-pyridyl)-, β-(3-pyridyl)- or β-(4-pyridyl)-L-alanine derivatives inthe above-described coupling reactions.

Additionally, when the R⁴ substituent of a compound of formula I or anintermediate thereof contains a primary or secondary amino group, suchamino groups can be further derivatized either before or after the abovecoupling reactions to provide, by way of example, amides, sulfonamides,ureas, thioureas, carbamates, secondary or tertiary amines and the like.Compounds having a primary amino group on the R⁴ substituent may beprepared, for example, by reduction of the corresponding nitro compoundas described above. Alternatively, such compounds can be prepared byusing an amino acid derivative of formula VI derived from lysine,4-aminophenylalanine and the like in the above-described couplingreactions.

By way of illustration, a compound of formula I or an intermediatethereof having a substituent containing a primary or secondary aminogroup, such as where R⁴ is a (4-aminophenyl)methyl group, can be readilyN-acylated using conventional acylating reagents and conditions toprovide the corresponding amide. This acylation reaction is typicallyconducted by treating the amino compound with at least one equivalent,preferably about 1.1 to about 1.2 equivalents, of a carboxylic acid inthe presence of a coupling reagent such as a carbodiimide, BOP reagent(benzotriazol-1-yloxy-tris(dimethylamino)phosphoniumhexafluorophosphonate) and the like, in an inert diluent, such asdichloromethane, chloroform, acetonitrile, tetrahydrofuran,N,N-dimethylformamide and the like, at a temperature ranging from about0° C. to about 37° C. for about 4 to about 24 hours. Preferably, apromoter, such as N-hydroxysuccinimide, 1-hydroxy-benzotriazole and thelike, is used to facilitate the acylation reaction. Examples ofcarboxylic acids suitable for use in this reaction include, but are notlimited to, N-tert-butyloxycarbonylglycine,N-tert-butyloxycarbonyl-L-phenylalanine,N-tert-butyloxycarbonyl-L-aspartic acid benzyl ester, benzoic acid,N-tert-butyloxycarbonylisonipecotic acid, N-methylisonipecotic acid,N-tert-butyloxycarbonylnipecotic acid,N-tert-butyloxycarbonyl-L-tetrahydroisoquinoline-3-carboxylic acid,N-(toluene4-sulfonyl)-L-proline and the like.

Alternatively, a compound of formula I or an intermediate thereofcontaining a primary or secondary amino group can be N-acylated using anacyl halide or a carboxylic acid anhydride to form the correspondingamide. This reaction is typically conducted by contacting the aminocompound with at least one equivalent, preferably about 1.1 to about 1.2equivalents, of the acyl halide or carboxylic acid anhydride in an inertdiluent, such as dichloromethane, at a temperature ranging from about ofabout −70° C. to about 40° C. for about 1 to about 24 hours. If desired,an acylation catalyst such as 4-(N,N-dimethylamino)pyridine may be usedto promote the acylation reaction. The acylation reaction is preferablyconducted in the presence of a suitable base to scavenge the acidgenerated during the reaction. Suitable bases include, by way ofexample, tertiary amines, such as triethylamine, diisopropylethylamine,N-methylmorpholine and the like. Alternatively, the reaction can beconducted under Schotten-Baumann-type conditions using aqueous alkali,such as sodium hydroxide and the like.

Examples of acyl halides and carboxylic acid anhydrides suitable for usein this reaction include, but are not limited to, 2-methylpropionylchloride, trimethylacetyl chloride, phenylacetyl chloride, benzoylchloride, 2-bromobenzoyl chloride, 2-methylbenzoyl chloride,2-trifluoro-methylbenzoyl chloride, isonicotinoyl chloride, nicotinoylchloride, picolinoyl chloride, acetic anhydride, succinic anhydride, andthe like. Carbamyl chlorides, such as N,N-dimethylcarbamyl chloride,N,N-diethylcarbamyl chloride and the like, can also be used in thisreaction to provide ureas. Similarly, dicarbonates, such asdi-tert-butyl dicarbonate, may be employed to provide carbamates.

In a similar manner, a compound of formula I or an intermediate thereofcontaining a primary or secondary amino group may be N-sulfonated toform a sulfonamide using a sulfonyl halide or a sulfonic acid anhydride.Sulfonyl halides and sulfonic acid anhydrides suitable for use in thisreaction include, but are not limited to, methanesulfonyl chloride,chloromethanesulfonyl chloride, p-toluenesulfonyl chloride,trifluoromethanesulfonic anhydride, and the like. Similarly, sulfamoylchlorides, such as dimethylsulfamoyl chloride, can be used to providesulfamides (e.g., >N—SO₂—N <).

Additionally, a primary and secondary amino group present on asubstituent of a compound of formula I or an intermediate thereof can bereacted with an isocyanate or a thioisocyanate to give a urea orthiourea, respectively. This reaction is typically conducted bycontacting the amino compound with at least one equivalent, preferablyabout 1.1 to about 1.2 equivalents, of the isocyanate or thioisocyanatein an inert diluent, such as toluene and the like, at a temperatureranging from about 24° C. to about 37° C. for about 12 to about 24hours. The isocyanates and thioisocyanates used in this reaction arecommercially available or can be prepared from commercially availablecompounds using well-known synthetic procedures. For example,isocyanates and thioisocyanates are readily prepared by reacting theappropriate amine with phosgene or thiophosgene. Examples of isocyanatesand thioisocyanates suitable for use in this reaction include, but arenot limited to, ethyl isocyanate, n-propyl isocyanate, 4-cyanophenylisocyanate, 3-methoxyphenyl isocyanate, 2-phenylethyl isocyanate, methylthioisocyanate, ethyl thioisocyanate, 2-phenylethyl thioisocyanate,3-phenylpropyl thioisocyanate, 3-(N,N-diethylamino)propylthioisocyanate, phenyl thioisocyanate, benzyl thioisocyanate, 3-pyridylthioisocyanate, fluorescein isothiocyanate (isomer I) and the like.

Furthermore, when a compound of formula I or an intermediate thereofcontains a primary or secondary amino group, the amino group can bereductively alkylated using aldehydes or ketones to form a secondary ortertiary amino group. This reaction is typically conducted by contactingthe amino compound with at least one equivalent, preferably about 1.1 toabout 1.5 equivalents, of an aldehyde or ketone and at least oneequivalent based on the amino compound of a metal hydride reducingagent, such as sodium cyanoborohydride, in an inert diluent, such asmethanol, tetrahydrofuran, mixtures thereof and the like, at atemperature ranging from about 0° C. to about 50° C. for about 1 toabout 72 hours. Aldehydes and ketones suitable for use in this reactioninclude, by way of example, benzaldehyde, 4-chlorobenzaldehyde,valeraldehyde and the like.

In a similar manner, when a compound of formula I or an intermediatethereof has a substituent containing a hydroxyl group, the hydroxylgroup can be further modified or derivatized either before or after theabove coupling reactions to provide, by way of example, ethers,carbamates and the like. Compounds having a hydroxyl group on the R⁴substituent, for example, can be prepared using an amino acid derivativeof formula V derived from tyrosine and the like in the above-describedreactions.

By way of example, a compound of formula I or an intermediate thereofhaving a substituent containing a hydroxyl group, such as where R⁴ is a(4-hydroxyphenyl)methyl group, can be readily O-alkylated to formethers. This O-alkylation reaction is typically conducted by contactingthe hydroxy compound with a suitable alkali or alkaline earth metalbase, such as potassium carbonate, in an inert diluent, such as acetone,2-butanone and the like, to form the alkali or alkaline earth metal saltof the hydroxyl group. This salt is generally not isolated, but isreacted in situ with at least one equivalent of an alkyl or substitutedalkyl halide or sulfonate, such as an alkyl chloride, bromide, iodide,mesylate or tosylate, to afford the ether. Generally, this reaction isconducted at a temperature ranging from about 60° C. to about 150° C.for about 24 to about 72 hours. Preferably, a catalytic amount of sodiumor potassium iodide is added to the reaction mixture when an alkylchloride or bromide is employed in the reaction.

Examples of alkyl or substituted alkyl halides and sulfonates suitablefor use in this reaction include, but are not limited to, tert-butylbromoacetate, N-tert-butyl chloroacetamide, 1-bromoethylbenzene, ethylα-bromophenylacetate, 2-(N-ethyl—N-phenylamino)ethyl chloride,2-(N,N-ethylamino)ethyl chloride, 2-(N,N-diisopropylamino)ethylchloride, 2-(N,N-dibenzylamino)ethyl chloride, 3-(N,N-ethylamino)propylchloride, 3-(N-benzyl—N-methylamino)propyl chloride,N-(2-chloroethyl)morpholine, 2-(hexamethyleneimino)ethyl chloride,3-(N-methylpiperazine)propyl chloride,1-(3-chlorophenyl)4-(3-chloropropyl)piperazine,2-(4-hydroxy-4-phenylpiperidine)ethyl chloride,N-tert-butyloxycarbonyl-3-piperidinemethyl tosylate, and the like.

Alternatively, a hydroxyl group present on a substituent of a compoundof formula I or an intermediate thereof can be O-alkylating using theMitsunobu reaction. In this reaction, an alcohol, such as3-(N,N-dimethylamino)-1-propanol and the like, is reacted with about 1.0to about 1.3 equivalents of triphenylphosphine and about 1.0 to about1.3 equivalents of diethyl azodicarboxylate in an inert diluent, such astetrahydrofuran, at a temperature ranging from about −10° C. to about 5°C. for about 0.25 to about 1 hour. About 1.0 to about 1.3 equivalents ofa hydroxy compound, such as N-tert-butyltyrosine methyl ester, is thenadded and the reaction mixture is stirred at a temperature of about 0°C. to about 30° C. for about 2 to about 48 hours to provide theO-alkylated product.

In a similar manner, a compound of formula I or an intermediate thereofcontaining an aryl hydroxy group can be reacted with an aryl iodide toprovide a diaryl ether. Generally, this reaction is conducted by formingthe alkali metal salt of the hydroxyl group using a suitable base, suchas sodium hydride, in an inert diluent such as xylenes at a temperatureof about −25° C. to about 10° C. The salt is then treated with about 1.1to about 1.5 equivalents of cuprous bromide dimethyl sulfide complex ata temperature ranging from about 10° C. to about 30° C. for about 0.5 toabout 2.0 hours, followed by about 1.1 to about 1.5 equivalents of anaryl iodide, such as sodium 2-iodobenzoate and the like. The reaction isthen heated to about 70° C. to about 150° C. for about 2 to about 24hours to provide the diaryl ether.

Additionally, a hydroxy-containing compound can also be readilyderivatized to form a carbamate. In one method for preparing suchcarbamates, a hydroxy compound of formula I or an intermediate thereofis contacted with about 1.0 to about 1.2 equivalents of 4-nitrophenylchloroformate in an inert diluent, such as dichloromethane, at atemperature ranging from about −25° C. to about 0° C. for about 0.5 toabout 2.0 hours. Treatment of the resulting carbonate with an excess,preferably about 2 to about 5 equivalents, of a trialkylamine, such astriethylamine, for about 0.5 to 2 hours, followed by about 1.0 to about1.5 equivalents of a primary or secondary amine provides the carbamate.Examples of amines suitable for using in this reaction include, but arenot limited to, piperazine, 1-methylpiperazine, 1-acetylpiperazine,morpholine, thiomorpholine, pyrrolidine, piperidine and the like.

Alternatively, in another method for preparing carbamates, ahydroxy-containing compound is contacted with about 1.0 to about 1.5equivalents of a carbamyl chloride in an inert diluent, such asdichloromethane, at a temperature ranging from about 25° C. to about 70°C. for about 2 to about 72 hours. Typically, this reaction is conductedin the presence of a suitable base to scavenge the acid generated duringthe reaction. Suitable bases include, by way of example, tertiaryamines, such as triethylamine, diisopropylethylamine, N-methylmorpholineand the like. Additionally, at least one equivalent (based on thehydroxy compound) of 4-(N,N-dimethylamino)pyridine is preferably addedto the reaction mixture to facilitate the reaction. Examples of carbamylchlorides suitable for use in this reaction include, by way of example,dimethylcarbamyl chloride, diethylcarbamyl chloride and the like.

Likewise, when a compound of formula I or an intermediate thereofcontains a primary or secondary hydroxyl group, such hydroxyl groups canbe readily converted into a leaving group and displaced to form, forexample, amines, sulfides and fluorides. For example, derivatives of4-hydroxy-L-proline can be converted into the corresponding 4-amino,4-thio or 4-fluoro-L-proline derivatives via nucleophilic displacementof the derivatized hydroxyl group. Generally, when a chiral compound isemployed in these reactions, the stereochemistry at the carbon atomattached to the derivatized hydroxyl group is typically inverted.

These reactions are typically conducted by first converting the hydroxylgroup into a leaving group, such as a tosylate, by treatment of thehydroxy compound with at least one equivalent of a sulfonyl halide, suchas p-toluenesulfonyl chloride and the like, in pyridine. This reactionis generally conducted at a temperature of from about 0° C. to about 70°C. for about 1 to about 48 hours. The resulting tosylate can then bereadily displaced with sodium azide, for example, by contacting thetosylate with at least one equivalent of sodium azide in an inertdiluent, such as a mixture of N,N-dimethylformamide and water, at atemperature ranging from about 0° C. to about 37° C. for about 1 toabout 12 hours to provide the corresponding azido compound. The azidogroup can then be reduced by, for example, hydrogenation using apalladium on carbon catalyst to provide the amino (—NH₂) compound.

Similarly, a tosylate group can be readily displaced by a thiol to forma sulfide. This reaction is typically conducted by contacting thetosylate with at least one equivalent of a thiol, such as thiophenol, inthe presence of a suitable base, such as1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), in an inert diluent, such asN,N-dimethylformamide, at a temperature of from about 0° C. to about 37°C. for about 1 to about 12 hours to provide the sulfide. Additionally,treatment of a tosylate with morpholinosulfur trifluoride in an inertdiluent, such as dichloromethane, at a temperature ranging from about 0°C. to about 37° C. for about 12 to about 24 hours affords thecorresponding fluoro compound.

Furthermore, a compound of formula I or an intermediate thereof having asubstituent containing an iodoaryl group, for example, when R⁴ is a(4-iodophenyl)methyl group, can be readily converted either before orafter the above coupling reactions into a biaryl compound. Typically,this reaction is conducted by treating the iodoaryl compound with about1.1 to about 2 equivalents of an arylzinc iodide, such as2-(methoxycarbonyl)phenylzinc iodide, in the presence of a palladiumcatalyst, such as palladium tetra(triphenylphosphine), in an inertdiluent, such as tetrahydrofuran, at a temperature ranging from about24° C. to about 30° C. until reaction completion. This reaction isfurther described, for example, in Rieke, J. Org. Chem. 1991, 56, 1445.

In some cases, the compounds of formula I or intermediates thereof maycontain substituents having one or more sulfur atoms. Such sulfur atomswill be present, for example, when the cyclic compound of formula IIemployed in the above reactions is derived from3-oxothiomorpholine-5-carboxylic acid and the like. When present, suchsulfur atoms can be oxidized either before or after the above couplingreactions to provide a sulfoxide or sulfone compound using conventionalreagents and reaction conditions. Suitable reagents for oxidizing asulfide compound to a sulfoxide include, by way of example, hydrogenperoxide, 3-chloroperoxybenzoic acid (MCPBA), sodium periodate and thelike. The oxidation reaction is typically conducted by contacting thesulfide compound with about 0.95 to about 1.1 equivalents of theoxidizing reagent in an inert diluent, such as dichloromethane, at atemperature ranging from about—50° C. to about 75° C. for about 1 toabout 24 hours. The resulting sulfoxide can then be further oxidized tothe corresponding sulfone by contacting the sulfoxide with at least oneadditional equivalent of an oxidizing reagent, such as hydrogenperoxide, MCPBA, potassium permanganate and the like. Alternatively, thesulfone can be prepared directly by contacting the sulfide with at leasttwo equivalents, and preferably an excess, of the oxidizing reagent.Such reactions are described further in March, “Advanced OrganicChemistry”, 4th Ed., pp. 1201-1202, Wiley Publisher, 1992.

Lastly, the compounds of formula I where W is sulfur can prepared byusing an thiocarbonyl derivative in place of compound II in the abovedescribed synthetic procedures. Such thiocarbonyl derivatives can beprepared using, for example, Lawesson's reagent under conventionalreaction conditions.

Other procedures and reaction conditions for preparing the compounds ofthis invention are described in the examples set forth below.

Pharmaceutical Formulations

When employed as pharmaceuticals, the compounds of formula I and IA areusually administered in the form of pharmaceutical compositions. Thesecompounds can be administered by a variety of routes including oral,rectal, transdermal, subcutaneous, intravenous, intramuscular, andintranasal. These compounds are effective as both injectable and oralcompositions. Such compositions are prepared in a manner well known inthe pharmaceutical art and comprise at least one active compound.

This invention also includes pharmaceutical compositions which contain,as the active ingredient, one or more of the compounds of formula I andIA above associated with pharmaceutically acceptable carriers. In makingthe compositions of this invention, the active ingredient is usuallymixed with an excipient, diluted by an excipient or enclosed within sucha carrier which can be in the form of a capsule, sachet, paper or othercontainer. When the excipient serves as a diluent, it can be a solid,semi-solid, or liquid material, which acts as a vehicle, carrier ormedium for the active ingredient. Thus, the compositions can be in theform of tablets, pills, powders, lozenges, sachets, cachets, elixirs,suspensions, emulsions, solutions, syrups, aerosols (as a solid or in aliquid medium), ointments containing, for example, up to 10% by weightof the active compound, soft and hard gelatin capsules, suppositories,sterile injectable solutions, and sterile packaged powders.

In preparing a formulation, it may be necessary to mill the activecompound to provide the appropriate particle size prior to combiningwith the other ingredients. If the active compound is substantiallyinsoluble, it ordinarily is milled to a particle size of less than 200mesh. If the active compound is substantially water soluble, theparticle size is normally adjusted by milling to provide a substantiallyuniform distribution in the formulation, e.g. about 40 mesh.

Some examples of suitable excipients include lactose, dextrose, sucrose,sorbitol, mannitol, starches, gum acacia, calcium phosphate, alginates,tragacanth, gelatin, calcium silicate, microcrystalline cellulose,polyvinylpyrrolidone, cellulose, water, syrup, and methyl cellulose. Theformulations can additionally include: lubricating agents such as talc,magnesium stearate, and mineral oil; wetting agents; emulsifying andsuspending agents; preserving agents such as methyl- andpropylhydroxy-benzoates; sweetening agents; and flavoring agents. Thecompositions of the invention can be formulated so as to provide quick,sustained or delayed release of the active ingredient afteradministration to the patient by employing procedures known in the art.

The compositions are preferably formulated in a unit dosage form, eachdosage containing from about 5 to about 100 mg, more usually about 10 toabout 30 mg, of the active ingredient. The term “unit dosage forms”refers to physically discrete units suitable as unitary dosages forhuman subjects and other mammals, each unit containing a predeterminedquantity of active material calculated to produce the desiredtherapeutic effect, in association with a suitable pharmaceuticalexcipient.

The active compound is effective over a wide dosage range and isgenerally administered in a pharmaceutically effective amount. It, willbe understood, however, that the amount of the compound actuallyadministered will be determined by a physician, in the light of therelevant circumstances, including the condition to be treated, thechosen route of administration, the actual compound administered, theage, weight, and response of the individual patient, the severity of thepatient's symptoms, and the like.

For preparing solid compositions such as tablets, the principal activeingredient is mixed with a pharmaceutical excipient to form a solidpreformulation composition containing a homogeneous mixture of acompound of the present invention. When referring to thesepreformulation compositions as homogeneous, it is meant that the activeingredient is dispersed evenly throughout the composition so that thecomposition may be readily subdivided into equally effective unit dosageforms such as tablets, pills and capsules. This solid preformulation isthen subdivided into unit dosage forms of the type described abovecontaining from, for example, 0.1 to about 500 mg of the activeingredient of the present invention.

The tablets or pills of the present invention may be coated or otherwisecompounded to provide a dosage form affording the advantage of prolongedaction. For example, the tablet or pill can comprise an inner dosage andan outer dosage component, the latter being in the form of an envelopeover the former. The two components can be separated by an enteric layerwhich serves to resist disintegration in the stomach and permit theinner component to pass intact into the duodenum or to be delayed inrelease. A variety of materials can be used for such enteric layers orcoatings, such materials including a number of polymeric acids andmixtures of polymeric acids with such materials as shellac, cetylalcohol, and cellulose acetate.

The liquid forms in which the novel compositions of the presentinvention may be incorporated for administration orally or by injectioninclude aqueous solutions suitably flavored syrups, aqueous or oilsuspensions, and flavored emulsions with edible oils such as cottonseedoil, sesame oil, coconut oil, or peanut oil, as well as elixirs andsimilar pharmaceutical vehicles.

Compositions for inhalation or insufflation include solutions andsuspensions in pharmaceutically acceptable, aqueous or organic solvents,or mixtures thereof, and powders. The liquid or solid compositions maycontain suitable pharmaceutically acceptable excipients as describedsupra. Preferably the compositions are administered by the oral or nasalrespiratory route for local or systemic effect. Compositions inpreferably pharmaceutically acceptable solvents may be nebulized by useof inert gases. Nebulized solutions may be breathed directly from thenebulizing device or the nebulizing device may be attached to a facemasks tent, or intermittent positive pressure breathing machine.Solution, suspension, or powder compositions may be administered,preferably orally or nasally, from devices which deliver the formulationin an appropriate manner.

The following formulation examples illustrate the pharmaceuticalcompositions of the present invention.

Formulation Example 1

Hard gelatin capsules containing the following ingredients are prepared:

Quantity Ingredient (mg/capsule) Active Ingredient 30.0 Starch 305.0Magnesium stearate 5.0

The above ingredients are mixed and filled into hard gelatin capsules in340 mg quantities.

Formulation Example 2

A tablet formula is prepared using the ingredients below:

Quantity Ingredient (mg/tablet) Active Ingredient 25.0 Cellulose,microcrystalline 200.0 Colloidal silicon dioxide 10.0 Stearic acid 5.0

The components are blended and compressed to form tablets, each weighing240 mg.

Formulation Example 3

A dry powder inhaler formulation is prepared containing the followingcomponents:

Ingredient Weight % Active Ingredient 5 Lactose 95

The active mixture is mixed with the lactose and the mixture is added toa dry powder inhaling appliance.

Formulation Example 4

Tablets, each containing 30 mg of active ingredient, are prepared asfollows:

Quantity Ingredient (mg/tablet) Active Ingredient 30.0 mg Starch 45.0 mgMicrocrystalline cellulose 35.0 mg Polyvinylpyrrolidone 4.0 mg (as 10%solution in water) Sodium carboxymethyl starch 4.5 mg Magnesium stearate0.5 mg Talc 1.0 mg Total 120 mg

The active ingredient, starch and cellulose are passed through a No. 20mesh U.S. sieve and mixed thoroughly. The solution ofpolyvinylpyrrolidone is mixed with the resultant powders, which are thenpassed through a 16 mesh U.S. sieve. The granules so produced are driedat 50° to 60° C. and passed through a 16 mesh U.S. sieve. The sodiumcarboxymethyl starch, magnesium stearate, and talc, previously passedthrough a No. 30 mesh U.S. sieve, are then added to the granules which,after mixing, are compressed on a tablet machine to yield tablets eachweighing 150 mg.

Formulation Example 5

Capsules, each containing 40 mg of medicament are made as follows:

Quantity Ingredient (mg/capsule) Active Ingredient 40.0 mg Starch 109.0mg Magnesium stearate 1.0 mg Total 150.0 mg

The active ingredient, cellulose, starch, an magnesium stearate areblended, passed through a No. 20 mesh U.S. sieve, and filled into hardgelatin capsules in 150 mg quantities.

Formulation Example 6

Suppositories, each containing 25 mg of active ingredient are made asfollows:

Ingredient Amount Active Ingredient 25 mg Saturated fatty acidglycerides to 2,000 mg

The active ingredient is passed through a No. 60 mesh U.S. sieve andsuspended in the saturated fatty acid glycerides previously melted usingthe minimum heat necessary. The mixture is then poured into asuppository mold of nominal 2.0 g capacity and allowed to cool.

Formulation Example 7

Suspensions, each containing 50 mg of medicament per 5.0 ml dose aremade as follows:

Ingredient Amount Active Ingredient 50.0 mg Xanthan gum  4.0 mg Sodiumcarboxymethyl cellulose (11%) 50.0 mg Microcrystalline cellulose (89%)Sucrose 1.75 g   Sodium benzoate 10.0 mg Flavor and Color q.v. Purifiedwater to  5.0 ml

The medicament, sucrose and xanthan gum are blended, passed through aNo. 10 mesh U.S. sieve, and then mixed with a previously made solutionof the microcrystalline cellulose and sodium carboxymethyl cellulose inwater. The sodium benzoate, flavor, and color are diluted with some ofthe water and added with stirring. Sufficient water is then added toproduce the required volume.

Formulation Example 8

Quantity Ingredient (mg/capsule) Active Ingredient 15.0 mg Starch 407.0mg Magnesium stearate 3.0 mg Total 425.0 mg

The active ingredient, cellulose, starch, and magnesium stearate areblended, passed through a No. 20 mesh U.S. sieve, and filled into hardgelatin capsules in 560 mg quantities.

Formulation Example 9

An intravenous formulation may be prepared as follows:

Ingredient Quantity Active Ingredient 250.0 mg Isotonic saline 1000 ml

Formulation Example 10

A topical formulation may be prepared as follows:

Ingredient Quantity Active Ingredient 1-10 g Emulsifying Wax 30 g LiquidParaffin 20 g White Soft Paraffin to 100 g

The white soft paraffin is heated until molten. The liquid paraffin andemulsifying wax are incorporated and stirred until dissolved. The activeingredient is added and stirring is continued until dispersed. Themixture is then cooled until solid.

Another preferred formulation employed in the methods of the presentinvention employs transdermal delivery devices (“patches”). Suchtransdermal patches may be used to provide continuous or discontinuousinfusion of the compounds of the present invention in controlledamounts. The construction and use of transdermal patches for thedelivery of pharmaceutical agents is well known in the art. See. e.g.,U.S. Pat. No. 5,023,252, issued Jun. 11, 1991, herein incorporated byreference. Such patches may be constructed for continuous, pulsatile, oron demand delivery of pharmaceutical agents.

Direct or indirect placement techniques may be used when it is desirableor necessary to introduce the pharmaceutical composition to the brain.Direct techniques usually involve placement of a drug delivery catheterinto the host's ventricular system to bypass the blood-brain barrier.One such implantable delivery system used for the transport ofbiological factors to specific anatomical regions of the body isdescribed in U.S. Pat. No. 5,011,472 which is herein incorporated byreference.

Indirect techniques, which are generally preferred, usually involveformulating the compositions to provide for drug latentiation by theconversion of hydrophilic drugs into lipid-soluble drugs. Latentiationis generally achieved through blocking of the hydroxy, carbonyl,sulfate, and primary amine groups present on the drug to render the drugmore lipid soluble and amenable to transportation across the blood-brainbarrier. Alternatively, the delivery of hydrophilic drugs may beenhanced by intra-arterial infusion of hypertonic solutions which cantransiently open the blood-brain barrier.

Utility

The compounds of this invention can be employed to bind VLA-4 (α₄β₁integrin) in biological samples and, accordingly have utility in, forexample, assaying such samples for VLA-4. In such assays, the compoundscan be bound to a solid support and the VLA-4 sample added thereto. Theamount of VLA-4 in the sample can be determined by conventional methodssuch as use of a sandwich ELISA assay. Alternatively, labeled VLA-4 canbe used in a competitive assay to measure for the presence of VLA-4 inthe sample. Other suitable assays are well known in the art.

In addition, certain of the compounds of this invention inhibit, invivo, adhesion of leukocytes to endothelial cells mediated by VLA-4 and,accordingly, can be used in the treatment of diseases mediated by VLA-4.Such diseases include inflammatory diseases in mammalian patients suchas asthma, Alzheimer's disease, atherosclerosis, AIDS dementia, diabetes(including acute juvenile onset diabetes), inflammatory bowel disease(including ulcerative colitis and Crohn's disease), multiple sclerosis,rheumatoid arthritis, tissue transplantation, tumor metastasis,meningitis, encephalitis, stroke, and other cerebral traumas, nephritis,retinitis, atopic dermatitis, psoriasis, myocardial ischemia and acuteleukocyte-mediated lung injury such as that which occurs in adultrespiratory distress syndrome.

The biological activity of the compounds identified above may be assayedin a variety of systems. For example, a compound can be immobilized on asolid surface and adhesion of cells expressing VLA-4 can be measured.Using such formats, large numbers of compounds can be screened. Cellssuitable for this assay include any leukocytes known to express VLA-4such as T cells, B cells, monocytes, eosinophils, and basophils. Anumber of leukocyte cell lines can also be used, examples include Jurkatand U937.

The test compounds can also be tested for the ability to competitivelyinhibit binding between VLA-4 and VCAM-1, or between VLA-4 and a labeledcompound known to bind VLA-4 such as a compound of this invention orantibodies to VLA-4. In these assays, the VCAM-1 can be immobilized on asolid surface. VCAM-1 may also be expressed as a recombinant fusionprotein having an Ig tail (e.g., IgG) so that binding to VLA-4 may bedetected in an immunoassay. Alternatively, VCAM-1 expressing cells, suchas activated endothelial cells or VCAM-1 transfected fibroblasts can beused. For assays to measure the ability to block adhesion to brainendothelial cells, the assays described in International PatentApplication Publication No. WO 91/05038 are particularly preferred. Thisapplication is incorporated herein by reference in its entirety.

Many assay formats employ labelled assay components. The labellingsystems can be in a variety of forms. The label may be coupled directlyor indirectly to the desired component of the assay according to methodswell known in the art. A wide variety of labels may be used. Thecomponent may be labelled by any one of several methods. The most commonmethod of detection is the use of autoradiography with ³H, ¹²⁵I, ³⁵S,¹⁴C, or ³²P labelled compounds or the like. Non-radioactive labelsinclude ligands which bind to labelled antibodies, fluorophores,chemiluminescent agents, enzymes and antibodies which can serve asspecific binding pair members for a labelled ligand. The choice of labeldepends on sensitivity required, ease of conjugation with the compound,stability requirements, and available instrumentation.

Appropriate in vivo models for demonstrating efficacy in treatinginflammatory responses include EAE (experimental autoimmuneencephalomyelitis) in mice, rats, guinea pigs or primates, as well asother inflammatory models dependent upon α4 integrins.

Compounds having the desired biological activity may be modified asnecessary to provide desired properties such as improved pharmacologicalproperties (e.g., in vivo stability, bio-availability), or the abilityto be detected in diagnostic applications. For instance, inclusion ofone or more D-amino acids in the sulfonamides of this inventiontypically increases in vivo stability. Stability can be assayed in avariety of ways such as by measuring the half-life of the proteinsduring incubation with peptidases or human plasma or serum. A number ofsuch protein stability assays have been described (see, e.g., Verhoef etal., Eur. J. Drug Metab. Pharmacokinet., 1990, 15(2):83-93).

For diagnostic purposes, a wide variety of labels may be linked to thecompounds, which may provide, directly or indirectly, a detectablesignal. Thus, the compounds of the subject invention may be modified ina variety ways for a variety of end purposes while still retainingbiological activity. addition, various reactive sites may be introducedat the terminus for linking to particles, solid substrates,macromolecules, or the like.

Labeled compounds can be used in a variety of in vivo or in vitroapplications. A wide variety of labels maybe employed, such asradionuclides (e.g., gamma-emitting radioisotopes such as technetium-99or indium-111), fluorescers (e.g., fluorescein), enzymes, enzymesubstrates, enzyme cofactors, enzyme inhibitors, chemiluminescentcompounds, bioluminescent compounds, and the like. Those of ordinaryskill in the art will know of other suitable labels for binding to thecomplexes, or will be able to ascertain such using routineexperimentation. The binding of these labels is achieved using standardtechniques common to those of ordinary skill in the art.

In vitro uses include diagnostic applications such as monitoringinflammatory responses by detecting the presence of leukocytesexpressing VLA-4. The compounds of this invention can also be used forisolating or labeling such cells. In addition, as mentioned above, thecompounds of the invention can be used to assay for potential inhibitorsof VLA-4/VCAM-1 interactions.

For in vivo diagnostic imaging to identify, e.g., sites of inflammation,radioisotopes are typically used in accordance with well knowntechniques. The radioisotopes may be bound to the peptide eitherdirectly or indirectly using intermediate functional groups. Forinstance, chelating agents such as diethylenetriaminepentacetic acid(DTPA) and ethylenediaminetetraacetic acid (EDTA) and similar moleculeshave been used to bind proteins to metallic ion radioisotopes.

The complexes can also be labeled with a paramagnetic isotope forpurposes of in vivo diagnosis, as in magnetic resonance imaging (MRI) orelectron spin resonance (ESR), both of which are well known. In general,any conventional method for visualizing diagnostic imaging can be used.Usually gamma- and positron-emitting radioisotopes are used for cameraimaging and paramagnetic isotopes are used for MRI. Thus, the compoundscan be used to monitor the course of amelioration of an inflammatoryresponse in an individual. By measuring the increase or decrease inlymphocytes expressing VLA-4 it is possible to determine whether aparticular therapeutic regimen aimed at ameliorating the disease iseffective.

The pharmaceutical compositions of the present invention can be used toblock or inhibit cellular adhesion associated with a number of diseasesand disorders. For instance, a number of inflammatory disorders areassociated with integrins or leukocytes. Treatable disorders include,e.g., transplantation rejection (e.g., allograft rejection), Alzheimer'sdisease, atherosclerosis, AIDS dementia, diabetes (including acutejuvenile onset diabetes), retinitis, cancer metastases, rheumatoidarthritis, acute leukocyte-mediated lung injury (e.g., adult respiratorydistress syndrome), asthma, nephritis, and acute and chronicinflammation, including atopic dermatitis, psoriasis, myocardialischemia, and inflammatory bowel disease (including Crohn's disease andulcerative colitis). In preferred embodiments the pharmaceuticalcompositions are used to treat inflammatory brain disorders, such asmultiple sclerosis (MS), viral meningitis and encephalitis.

Inflammatory bowel disease is a collective term for two similar diseasesreferred to as Crohn's disease and ulcerative colitis. Crohn's diseaseis an idiopathic, chronic ulceroconstrictive inflammatory diseasecharacterized by sharply delimited and typically transmural involvementof all layers of the bowel wall by a granulomatous inflammatoryreaction. Any segment of the gastrointestinal tract, from the mouth tothe anus, may be involved, although the disease most commonly affectsthe terminal ileum and/or colon. Ulcerative colitis is an inflammatoryresponse limited largely to the colonic mucosa and submucosa.Lymphocytes and macrophages are numerous in lesions of inflammatorybowel disease and may contribute to inflammatory injury.

Asthma is a disease characterized by increased responsiveness of thetracheobronchial tree to various stimuli potentiating paroxysmalconstriction of the bronchial airways. The stimuli cause release ofvarious mediators of inflammation from IgE-coated mast cells includinghistamine, eosinophilic and neutrophilic chemotactic factors,leukotrines, prostaglandin and platelet activating factor. Release ofthese factors recruits basophils, eosinophils and neutrophils, whichcause inflammatory injury.

Atherosclerosis is a disease of arteries (e.g., coronary, carotid, aortaand iliac). The basic lesion, the atheroma, consists of a raised focalplaque within the intima, having a core of lipid and a covering fibrouscap. Atheromas compromise arterial blood flow and weaken affectedarteries. Myocardial and cerebral infarcts are a major consequence ofthis disease. Macrophages and leukocytes are recruited to atheromas andcontribute to inflammatory injury.

Rheumatoid arthritis is a chronic, relapsing inflammatory disease thatprimarily causes impairment and destruction of joints. Rheumatoidarthritis usually first affects the small joints of the hands and feetbut then may involve the wrists, elbows, ankles and knees. The arthritisresults from interaction of synovial cells with leukocytes thatinfiltrate from the circulation into the synovial lining of the joints.See e.g., Paul, Immunology (3d ed., Raven Press, 1993).

Another indication for the compounds of this invention is in treatmentof organ or graft rejection mediated by VLA-4. Over recent years therehas been a considerable improvement in the efficiency of surgicaltechniques for transplanting tissues and organs such as skin, kidney,liver, heart, lung, pancreas and bone marrow. Perhaps the principaloutstanding problem is the lack of satisfactory agents for inducingimmunotolerance in the recipient to the transplanted allograft or organ.When allogeneic cells or organs are transplanted into a host (i.e., thedonor and donee are different individuals from the same species), thehost immune system is likely to mount an immune response to foreignantigens in the transplant (host-versus-graft disease) leading todestruction of the transplanted tissue. CD8⁺ cells, CD4 cells andmonocytes are all involved in the rejection of transplant tissues.Compounds of this invention which bind to alpha-4 integrin are useful,inter alia, to block alloantigen-induced immune responses in the doneethereby preventing such cells from participating in the destruction ofthe transplanted tissue or organ. See, e.g., Paul et al., TransplantInternational 9, 420-425 (1996); Georczynski et al., Immunology 87,573-580 (1996); Georcyznski et al., Transplant. Immunol. 3, 55-61(1995); Yang et al., Transplantation 60, 71-76 (1995); Anderson et al.,APMIS 102, 23-27 (1994).

A related use for compounds of this invention which bind to VLA-4 is inmodulating the immune response involved in “graft versus host” disease(GVHD). See e.g., Schlegel et al., J. Immunol. 155, 3856-3865 (1995).GVHD is a potentially fatal disease that occurs when immunologicallycompetent cells are transferred to an allogeneic recipient. In thissituation, the donor's immunocompetent cells may attack tissues in therecipient. Tissues of the skin, gut epithelia and liver are frequenttargets and may be destroyed during the course of GVHD. The diseasepresents an especially severe problem when immune tissue is beingtransplanted, such as in bone marrow transplantation; but less severeGVHD has also been reported in other cases as well, including heart andliver transplants. The therapeutic agents of the present invention areused, inter alia, to block activation of the donor T-cells therebyinterfering with their ability to lyse target cells in the host.

A further use of the compounds of this invention is inhibiting tumormetastasis. Several tumor cells have been reported to express VLA-4 andcompounds which bind VLA-4 block adhesion of such cells to endothelialcells. Steinback et al., Urol. Res. 23, 175-83 (1995); Orosz et al.,Int. J. Cancer 60, 867-71 (1995); Freedman et al., Leuk. Lymphoma 13,47-52 (1994); Okahara et al., Cancer Res. 54, 3233-6 (1994).

A further use of the compounds of this invention is in treating multiplesclerosis. Multiple sclerosis is a progressive neurological autoimmunedisease that affects an estimated 250,000 to 350,000 people in theUnited States. Multiple sclerosis is thought to be the result of aspecific autoimmune reaction in which certain leukocytes attack andinitiate the destruction of myelin, the insulating sheath covering nervefibers. In an animal model for multiple sclerosis, murine monoclonalantibodies directed against VLA-4 have been shown to block the adhesionof leukocytes to the endothelium, and thus prevent inflammation of thecentral nervous system and subsequent paralysis in the animals¹⁶.

Pharmaceutical compositions of the invention are suitable for use in avariety of drug delivery systems. Suitable formulations for use in thepresent invention are found in Remington's Pharmaceutical Sciences, MacePublishing Company, Philadelphia, Pa., 17th ed. (1985).

In order to enhance serum half-life, the compounds may be encapsulated,introduced into the lumen of liposomes, prepared as a colloid, or otherconventional techniques may be employed which provide an extended serumhalf-life of the compounds. A variety of methods are available forpreparing liposomes, as described in, e.g., Szoka, et al., U.S. Pat.Nos. 4,235,871, 4,501,728 and 4,837,028 each of which is incorporatedherein by reference.

The amount administered to the patient will vary depending upon what isbeing administered, the purpose of the administration, such asprophylaxis or therapy, the state of the patient, the manner ofadministration, and the like. In therapeutic applications, compositionsare administered to a patient already suffering from a disease in anamount sufficient to cure or at least partially arrest the symptoms ofthe disease and its complications. An amount adequate to accomplish thisis defined as “therapeutically effective dose.” Amounts effective forthis use will depend on the disease condition being treated as well asby the judgment of the attending clinician depending upon factors suchas the severity of the inflammation, the age, weight and generalcondition of the patient, and the like.

The compositions administered to a patient are in the form ofpharmaceutical compositions described above. These compositions may besterilized by conventional sterilization techniques, or may be sterilefiltered. The resulting aqueous solutions may be packaged for use as is,or lyophilized, the lyophilized preparation being combined with asterile aqueous carrier prior to administration. The pH of the compoundpreparations typically will be between 3 and 11, more preferably from 5to 9 and most preferably from 7 to 8. It will be understood that use ofcertain of the foregoing excipients, carriers, or stabilizers willresult in the formation of pharmaceutical salts.

The therapeutic dosage of the compounds of the present invention willvary according to, for example, the particular use for which thetreatment is made, the manner of administration of the compound, thehealth and condition of the patient, and the judgment of the prescribingphysician. For example, for intravenous administration, the dose willtypically be in the range of about 20 μg to about 500 μg per kilogrambody weight, preferably about 100 μg to about 300 μg per kilogram bodyweight. Suitable dosage ranges for intranasal administration aregenerally about 0.1 pg to 1 mg per kilogram body weight. Effective dosescan be extrapolated from dose-response curves derived from in vitro oranimal model test systems.

The following synthetic and biological examples are offered toillustrate this invention and are not to be construed in any way aslimiting the scope of this invention. Unless otherwise stated, alltemperatures are in degrees Celsius.

EXAMPLES

In the examples below, the following abbreviations have the followingmeanings. If an abbreviation is not defined, it has its generallyaccepted meaning.

aq or aq. = aqueous AcOH = acetic acid bd = broad doublet bm = broadmultiplet bs = broad singlet Bn = benzyl Boc = N-tert-butoxylcarbonylBoc₂O = di-tert-butyl dicarbonate BOP =benzotriazol-1-yloxy-tris(dimethylamino)phosphonium hexafluorophosphateCbz = carbobenzyloxy CHCl₃ = chloroform CH₂Cl₂ = dichloromethane (COCl)₂= oxalyl chloride d = doublet dd = doublet of doublets dt = doublet oftriplets DBU = 1,8-diazabicyclo[5.4.0]undec-7-ene DCC =1,3-dicyclohexylcarbodiimide DMAP = 4-N,N-dimethylaminopyridine DME =ethylene glycol dimethyl ether DMF = N,N-dimethylformamide DMSO =dimethylsulfoxide EDC = 1-(3-dimethylaminopropyl)-3-ethylcarbodiimidehydrochloride Et₃N = triethylamine Et₂O = diethyl ether EtOAc = ethylacetate EtOH = ethanol eq or eq. = equivalent Fmoc =N-(9-fluorenylmethoxycarbonyl) FmocONSu =N-(9-fluorenylmethoxycarbonyl)-succinimide g = grams h = hour H₂O =water HBr = hydrobromic acid HCl = hydrochloric acid HOBT =1-hydroxybenzotriazole hydrate hr = hour K₂CO₃ = potassium carbonate L =liter m = multiplet MeOH = methanol mg = milligram MgSO₄ = magnesiumsulfate mL = milliliter mm = millimeter mM = millimolar mmol = millimolmp = melting point N = normal NaCl = sodium chloride Na₂CO₃ = sodiumcarbonate NaHCO₃ = sodium bicarbonate NaOEt = sodium ethoxide NaOH =sodium hydroxide NH₄Cl = ammonium chloride NMM = N-methylmorpholine Phe= L-phenylalanine Pro = L-proline psi = pounds per square inch PtO₂ =platinum oxide q = quartet quint. = quintet rt = room temperature s =singlet sat = saturated t = triplet t-BuOH = tert-butanol TFA =trifluoroacetic acid THF = tetrahydrofuran TLC or tlc = thin layerchromatography Ts = tosyl TsCl = tosyl chloride TsOH = tosylate μL =microliter

The following Methods may be used to prepare the compounds of thisinvention.

Method A Methyl Ester Preparation Procedure

Amino acid methyl esters can be prepared using the method of Brenner andHuber Helv. Chim. Acta 1953, 36, 1109.

Method B BOP Coupling Procedure

The desired dipeptide ester was prepared by the reaction of a carboxylicacid (1 equivalent) with the appropriate amino acid ester or amino acidester hydrochloride (1 equivalent),benzotriazol-1-yloxytris(dimethylamino)phosphonium hexafluorophosphate[BOP] (2.0 equivalent), triethylamine (1.1 equivalent), and DMF. Thereaction mixture was stirred at room temperature overnight. The crudeproduct is purified flash chromatography to afford the dipeptide ester.

Method C Hydrogenation Procedure I

Hydrogenation was performed using 10% palladium on carbon (10% byweight) in methanol at 30 psi overnight. The mixture was filteredthrough a pad of Celite and the filtrate concentrated to yield thedesired compound.

Method D Hydrolysis Procedure I

To a chilled (0° C.) THF/H₂O solution (2:1, 5-10 mL) of the appropriateester was added LiOH (or NaOH) (0.95 equivalents). The temperature wasmaintained at 0° C. and the reaction was complete in 1-3 hours. Thereaction mixture was extracted with ethyl acetate and the aqueous phasewas lyophilized resulting in the desired carboxylate salt.

Method E Ester Hydrolysis Procedure II

To a chilled (0° C.) THF/H₂O solution (2:1, 5-10 mL) of the appropriateester was added LiOH (1.1 equivalents). The temperature was maintainedat 0° C. and the reaction was complete in 1-3 hours. The reactionmixture was concentrated and the residue was taken up into H₂O and thepH adjusted to 2-3 with aqueous HCl. The product was extracted withethyl acetate and the combined organic phase was washed with brine,dried over MgSO₄, filtered and concentrated to yield the desired acid.

Method F Ester Hydrolysis Procedure III

The appropriate ester was dissolved in dioxane/H₂O (1:1) and 0.9equivalents of 0.5 N NaOH was added. The reaction was stirred for 3-16hours and then concentrated. The resulting residue was dissolved in H₂Oand extracted with ethyl acetate. The aqueous phase was lyophilized toyield the desired carboxylate sodium salt.

Method G BOC Removal Procedure

Anhydrous hydrochloride (HCl) gas was bubbled through a methanolicsolution of the appropriate Boc-amino acid ester at 0° C. for 15 minutesand the reaction mixture was stirred for three hours. The solution wasconcentrated to a syrup and dissolved in Et₂O and reconcentrated. Thisprocedure was repeated and the resulting solid was placed under highvacuum overnight.

Method H tert-Butyl Ester Hydrolysis Procedure I

The tert-butyl ester was dissolved in CH₂Cl₂ and treated with TFA. Thereaction was complete in 1-3 hr at which time the reaction mixture wasconcentrated and the residue dissolved in H₂O and lyophilized to yieldthe desired acid.

Method I EDC Coupling Procedure I

To a CH₂Cl₂ solution (5-20 mL) of a carboxylic acid (1 equivalent), theappropriate amino acid ester hydrochloride (1 equivalent),N-methylmorpholine (1.1-2.2 equivalents) and 1-hydroxybenzotriazole (2equivalents) were mixed, placed in an ice bath and1-(3-dimethylaminopropyl)-3-ethyl carbodiimide (1.1 equivalents) added.The reaction was allowed to rise to room temperature and stirredovernight. The reaction mixture was poured into H₂O and the organicphase was washed with sat. NaHCO₃, brine, dried (MgSO₄ or Na₂SO₄),filtered and concentrated. The crude product was purified by columnchromatography.

Method J EDC Coupling Procedure II

To a DMF solution (5-20 mL) of a carboxylic acid (1 equivalent), theappropriated amino acid ester hydrochloride (1 equivalent), Et₃N (1.1equivalents) and 1-hydroxybenzotriazole (2 equivalents) were mixed,placed in an ice bath and 1-(3-dimethylaminopropyl)-3-ethyl carbodiimide(1.1 equivalents) added. The reaction was allowed to rise to roomtemperature and stirred overnight. The reaction mixture was partitionedbetween EtOAc and H₂O and the organic phase washed with 0.2 N citricacid, H₂O, sat. NaHCO₃, brine, dried (MgSO₄ or Na₂SO₄), filtered andconcentrated. The crude product was purified by column chromatography orpreparative TLC.

Method K tert-Butyl Ester Hydrolysis Procedure II

The tert-butyl ester was dissolved in CH₂Cl₂ (5 mL) and treated with TFA(5 mL). The reaction was complete in 1-3 hours at which time thereaction mixture was concentrated and the residue dissolved in H₂O andconcentrated. The residue was redissolved in H₂O and lyophilized toyield the desired product.

Method L Carbamate Formation Procedure I

Into a reaction vial were combined 15.2 mmol, 1.0 eq. of the startinghydroxy compound (typically a tyrosine derivative) and 1.86 g (15.2mmol, 1.0 eq) DMAP. Methylene chloride (50 mL), triethylamine (2.12 mL,1.54 g, 15.2 mmol, 1.0 eq), and dimethylcarbamyl chloride (1.68 mL, 1.96g, 18.2 mmol, 1.2 eq) were then added. The vial was capped tightly, andthe reaction solution swirled to obtain a homogeneous solution. Thereaction solution was then heated to 40° C. After 48 h, TLC of theresulting colorless solution indicated complete conversion. The work-upof the reaction solution was as follows: 50 mL EtOAc and 50 mL hexaneswas added to the reaction mixture, and the resulting mixture was washedwith 0.5 M citric acid (3×50 mL), water (2×50 mL), 10% K₂CO₃ (2×50 mL),and sat. NaCl (1×50 mL); dried with MgSO₄, filtered and evaporated toafford the desired compound.

Method M Carbamate Formation Procedure II

Into a reaction vial were combined 84.34 mmol (1.0 eq) of the startinghydroxy compound (typically a tyrosine derivative) and 17.0 g (84.34mmol, 1.0 eq) 4-nitrophenyl chloroformate. Methylene chloride (700 mL)was added and the vial was capped with a septum. A nitrogen line wasattached and the vial was immersed in a 4:1 water/ethanol dry ice slurrywith stirring to cool to −15° C. Triethylamine (29.38 mL, 21.33 g,210.81 mmol, 2.5 eq) was added over five minutes with stirring and thestirring was continued at −10 to −15° C. for 1 h. N-Methyl piperazine(9.35 mL, 8.45 g, 84.34 mmol, 1.0 eq) was added over three minutes withstirring and stirring was continued overnight while warming to roomtemperature. The reaction mixture was diluted with 700 mL hexanes andthe resulting mixture was washed repeatedly with 10% K₂CO₃, until noyellow color (from 4-nitrophenol) is observed in the aqueous layer. Themixture was then washed with sat. NaCl, dried over anhydrous MgSO₄,filtered and evaporated. The residue was dissolved in 500 mL of ethanoland evaporated to remove triethylamine. The residue was again dissolvedin 500 mL of ethanol and evaporated to remove triethylamine. The residuewas then dissolved in 400 mL of ethanol and 600 mL of water was addedwith stirring to precipitate a solid or oil. If an oil if formed, theoil is stirred vigorously to induce it to solidify. The solid is thenisolated by filtration. Dissolution, precipitation, and filtration arerepeated once and the resulting solid is rinsed with water to removetraces of yellow color. The solid is then subjected to high vacuum untilthe mass remains constant thereby affording the desired carbamyloxycompound.

Method N tert-Butyl Ester Hydrolysis Procedure III

A solution of the tert-butyl ester (typically 0.95 mmol) in 25 mL offormic acid was stirred at 25° C. for 24 hr. The solvent was removed andthe residue was washed with diethyl ether (3×) to afford the desiredproduct as a white solid.

Example 1 Synthesis of N-Benzyl-L-pyroglutamyl-L-phenylalanine

Step A—Preparation of N-Benzyl-L-pyroglutamic Acid Ethyl Ester

Ethyl (S)-(+)-2-pyrrolidone-5-carboxylate (1 g, 6.36 mmol) and benzylbromide (0.76 mL, 6.36 mmol) were placed in dry THF (30 mL). Thereaction mixture was stirred and cooled to 0° C. A 1M solultion oftert-BuOK was added dropwise (6.36 mL, 6.36 mmol) and the reaction wasstirred for an additional 0.5 h at 0° C. and allowed to come to roomtemperate where it was stirred for 24 hours under N₂. The reaction wasthen dissolved into a 1:1 mixture of H₂O/EtOAc. The organic layer waswashed with 1M HCl, H₂O and brine, and then dried over MgSO₄ to affordN-benzyl-L-pyroglutamic acid ethyl ester an oil.

Step B—Preparation of N-Benzyl-L-pyroglutamic Acid

The ester from Step A was then hydrolyzed using the procedure describedin Method F to afford N-benzyl-L-pyroglutamic acid.

Step C—Preparation of N-Benzyl-L-pyroglutamyl-L-phenylalanine EthylEster

The product from Step B was then coupled with L-phenylalanine ethylester using the procedure described in Method B (with substitution ofN-methylmorpholine for triethylamine) to affordN-Benzyl-L-pyroglutamyl-L-phenylalanine ethyl ester.

NMR data was as follows:

¹H NMR (CDCl₃): δ 7.29 (m, 6H), 7.10 (m, 4H), 6.28 (brd, 1H), 5.13 (d,1H), 4.90 (m, 1H), 4.19 (q, 2H), 3.77 (m, 2H), 3.29-2.98 (m, 2H), 2.37(m, 2H), 2.16 (m, 1H), 1.82 (m, 1H), 1.28 (t, 3H). ¹³C NMR (CDCl₃): δ176.18 171.84, 171.49, 136.32, 136.19, 129.67, 129.37, 129.31, 129.25,129.01, 128.41, 127.87, 62.38, 60.58, 53.24, 45.89, 38.24, 30.12, 23.84,14.74.

Step D—Preparation of N-Benzyl-L-pyroglutamyl-L-phenylalanine

The title compound was prepared by hydrolysis of the product from Step Cusing the procedure described in Method F.

NMR data was as follows:

¹H NMR (CDCl₃): δ 7.28 (m, 6H), 7.11 (m, 4H), 6.67 (brd, 1H), 5.07 (d,1H), 4.97 (m, 1H), 3.83 (m, 1H), 3.71 (d, 1H), 3.30 (m, 1H), 3.00 (m,1H), 2.38 (m, 2H), 2.16 (m, 1H), 1.73 (m, 1H).

Example 2 Synthesis ofN-Benzyloxycarbonyl-L-pyroglutamyl-L-phenylalanine

N-Benzyloxycarbonyl-L-pyroglutamyl-L-phenylalanine tert-butyl ester wasprepared from the appropriate starting materials using the proceduredescribed in Method B. The title compound was then prepared using theprocedure described in Method D.

NMR data was as follows:

¹H NMR (CDCl₃): δ 7.40-6.92 (m, 1H), 5.19 (s, 2H), 4.93 (m, 1H), 4.55(m, 1H), 3.25-2.89 (m, 2H), 2.42 (m, 2H), 2.16 (m, 1H), 1.94 (m, 1H).¹³C NMR (CDCl₃): δ 175.1 174.6 171.0, 151.8, 136.4, 135.3, 129.9, 129.2,129.1, 129.1, 128.8, 127.7, 69.2, 60.6, 53.4, 38.0, 31.8, 22.9.

Example 3 Synthesis ofN-Benzyl-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalanine

The title compound was prepared from the appropriate starting materialsusing the procedures described in Examples 1 and 4.

NMR data was as follows:

¹H NMR (DMSO-d₆): δ 10.24 (s, 1H), 8.53 (d, 1H), 7.93 (d, 2H), 7.74 (d,2H), 7.64-7.49 (m, 3H), 7.35-7.16 (m, 5H), 7.05 (d, 2H), 4.78 (d, 1H),4.54 (m, 1H), 3.88 (m, 1H), 3.20-2.78 (m, 2H), 2.22 (m, 2H), 2.12 (m,1H), 1.73 (m, 1H). ¹³C NMR (DMSO-d₆): δ 175.0, 172.9, 171.3, 165.8,137.7, 136.5, 135.0, 132.7, 131.5, 129.2, 128.5, 128.4, 127.8, 127.6,127.3, 58.8, 53.2, 44.2, 36.0, 29.3, 22.3.

Example 4 Synthesis ofN-(3,4-Dichlorobenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalanine

Step A—Preparation ofN-(3,4-Dichlorobenzyl)-L-pyroglutamyl-L-4-aminophenylalanine MethylEster

N-(3,4-Dichlorobenzyl)-L-pyroglutamyl-L-4-aminophenylalanine methylester was prepared from the appropriate starting materials using theprocedures described in Methods B and C.

Step B—Preparation ofN-(3,4-Dichlorobenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalanineMethyl Ester

The ester from Step A (230 mg, 0.495 mmol) was then placed in pyridineand benzoyl chloride (63.2 mL, 0.545 mmol) was added dropwise and thereaction was stirred for 2 hours. The resulting mixture was evaporatedto dryness and taken up in EtOAc. The organic layer was washed with H₂O,1M HCl, brine, and dried over MgSO₄ to giveN-(3,4-dichlorobenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)-phenylalaninemethyl ester as a white solid.

Step C—Preparation ofN-(3,4-Dichlorobenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalanineMethyl Ester

The title compound was prepared by hydrolyzing the product from Step Busing the procedure described in Method F.

NMR data was as follows:

¹H NMR (DMSO-d₆): δ 10.22 (s, 1H), 8.56 (brd, 1H), 7.93 (d, 2H), 7.68(d, 2H), 7.56 (m, 4H), 7.31 (s, 1H), 7.20 (d, 2H), 7.00 (d, 1H), 4.60(d, 1H), 4.53 (m, 1H), 3.96 (m, 1H), 3.42 (d, 1H), 3.16-2.79 (m, 2H),2.32 (m, 2H), 2.19 (m, 1H), 1.79 (m, 1H). ¹³C NMR (DMSO-d₆): δ 175.4,173.0, 171.1, 166.0, 138.1, 138.0, 135.4, 133.1, 132.0, 131.5, 130.9,130.1, 129.8, 129.1, 128.4, 128.3, 127.6, 120.4, 59.4, 53.4, 43.7, 36.5,29.6, 22.1.

Example 5 Synthesis ofN-(3-Chlorobenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalanineMethyl Ester

The title compound was prepared from the appropriate starting materialsusing the procedure described in Example 4.

NMR data was as follows:

¹H NMR (DMSO-d₆): δ 10.23 (s, 1H), 8.67 (d, 1H), 7.92 (d, 2H), 7.70 (d,2H), 7.52 (m, 3H), 7.31 (m, 2H), 7.19 (m, 3H), 6.98 (m, 2H), 4.68 (d,1H), 4.58 (m, 1H), 3.93 (m, 1H), 3.65 (s, 3H), 3.41 (d, 1H), 3.11-2.82(m, 2H), 2.30 (m, 2H), 2.15 (m, 1H), 1.77 (m, 1H).

Example 6 Synthesis ofN-(3-Chlorobenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalanine

The title compound was prepared from the product of Example 5 using theprocedure described in Method F.

NMR data was as follows:

¹H NMR (DMSO-d₆): δ 10.23 (s, 1H), 8.67 (d, 1H), 7.92 (d, 2H), 7.70 (d,2H), 7.52 (m, 3H), 7.31 (m, 2H), 7.19 (m, 3H), 6.98 (m, 2H), 4.68 (d,1H), 4.58 (m, 1H), 3.93 (m, 1H), 3.41 (d, 1H), 3.11-2.82 (m, 2H), 2.30(m, 2H), 2.15 (m, 1H), 1.77 (m, 1H).

Example 7 Synthesis ofN-(4-Chlorobenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalanine

The title compound was prepared from the product of Example 8 using theprocedure described in Method F.

NMR data was as follows:

¹H NMR (DMSO-d₆): δ 10.25 (s, 1H), 8.51 (d, 1H), 7.93 (d, 2H), 7.72 (d,2H), 7.54 (m, 3H), 7.33 (d, 2H), 7.20 (d, 2H), 7.01 (d, 2H), 4.67 (d,1H), 4.52 (m, 1H), 3.85 (m, 1H), 3.15-2.77 (m, 2H), 2.30 (m, 2H), 2.11(m, 1H), 1.76 (m, 1H).

Example 8 Synthesis ofN-(4-Chlorobenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalanineMethyl Ester

The title compound was prepared from the appropriate starting materialsusing the procedure described in Example 4.

NMR data was as follows:

¹H NMR (DMSO-d₆): δ 10.25 (s, 1H), 8.51 (d, 1H), 7.93 (d, 2H), 7.72 (d,2H), 7.54 (m, 3H), 7.33 (d, 2H), 7.20 (d, 2H), 7.01 (d, 2H), 4.67 (d,1H), 4.52 (m, 1H), 3.85 (m, 1H), 3.65 (s, 3H), 3.15-2.77 (m, 2H), 2.30(m, 2H), 2.11 (m, 1H), 1.76 (m, 1H).

Example 9 Synthesis ofN-(4-Methylbenzyl)-L-pyroglutamyl-L-(4-phenylcarbonylamino)phenylalanineMethyl Ester

The title compound was prepared from the appropriate starting materialsusing the procedure described in Example 4.

NMR data was as follows:

¹H NMR (DMSO-d₆): δ 10.25 (s, 1H), 8.59 (d, 1H), 7.94 (d, 2H), 7.74 (d,2H), 7.55 (m, 3H), 7.20 (d, 2H), 7.09 (d, 2H), 6.89 (d, 2H), 4.73 (d,1H), 4.60 (m, 1H), 3.82 (m, 1H), 3.66 (s, 3H), 3.32 (d, 1H), 3.13-2.81(m, 2H), 2.30 (m, 2H), 2.24 (s, 3H), 2.10 (m, 1H), 1.73 (m, 1H).

Example 10 Synthesis ofN-(4-Methylbenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalanine

The title compound was prepared from the product of Example 9 using theprocedure described in Method F.

NMR data was as follows:

¹H NMR (DMSO-d₆): δ 10.25 (s, 1H), 8.59 (d, 1H), 7.94 (d, 2H), 7.74 (d,2H), 7.55 (m, 3H), 7.20 (d, 2H), 7.09 (d, 2H), 6.89 (d, 2H), 4.73 (d,1H), 4.60 (m, 1H), 3.82 (m, 1H), 3.32 (d, 1H), 3.13-2.81 (m, 2H), 2.30(m, 2H), 2.24 (s, 3H), 2.10 (m, 1H), 1.73 (m, 1H).

Example 11 Synthesis ofN-(4-Methoxybenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalanineMethyl Ester

The title compound was prepared from the appropriate starting materialsusing the procedures described in Example 4.

NMR data was as follows:

¹H NMR (DMSO-d₆): δ 10.25 (s, 1H), 8.59 (d, 1H), 7.94 (d, 2H), 7.74 (d,2H), 7.55 (m, 3H), 7.42 (d, 2H), 6.92 (d, 2H), 6.83 (d, 2H), 4.73 (d,1H), 4.60 (m, 1H), 3.83 (m, 1H), 3.70 (s, 3H), 3.65 (s, 3H), 3.32 (d,1H), 3.16-2.81 (m, 2H), 2.30 (m, 2H), 2.10 (m, 1H), 1.73 (m, 1H). ¹³CNMR (DMSO-d₆): δ 174.8, 172.2, 171.6, 165.9, 158.9, 138.2, 136.4, 132.7,131.9, 129.6, 129.6, 128.8, 128.6, 128.0, 120.4, 114.3, 58.8, 55.4,53.5, 52.5, 44.0, 36.2, 29.6, 22.8.

Example 12 Synthesis ofN-(4-Methoxybenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalanine

The title compound was prepared from the product of Example 11 using theprocedure described in Method F.

NMR data was as follows:

¹H NMR (DMSO-d₆): δ 10.25 (s, 1H), 8.59 (d, 1H), 7.94 (d, 2H), 7.74 (d,2H), 7.55 (m, 3H), 7.42 (d, 2H), 6.92 (d, 2H), 6.83 (d, 2H), 4.73 (d,1H), 4.60 (m, 1H), 3.83 (m, 1H), 3.70 (s, 3H), 3.32 (d, 1H), 3.16-2.81(m, 2H), 2.30 (m, 2H), 2.10 (m, 1H), 1.73 (m, 1H).

Example 13 Synthesis ofN-(3-Chlorobenzyl)-L-pyroglutamyl-L-(N′-benzyl)histidine

N-(3-Chlorobenzyl)-L-pyroglutamyl-L-(N′-benzyl)histidine methyl esterwas prepared from the appropriate starting materials using the proceduredescribed in Method B. The title compound was then prepared byhydrolysis of the methyl ester using the procedure described in MethodE.

NMR data was as follows:

¹H NMR (DMSO-d₆): δ 8.08 (brd, 1H), 7.59 (s, 1H), 7.38-7.12 (m, 8H),7.05 (s, 1H), 6.84 (s, 1H), 5.08 (m, 2H), 4.68 (d, 1H), 4.27 (m, 1H),3.97 (m, 1H), 3.59 (d, 1H), 3.05-2.70 (m, 2H), 2.26 (m, 2h), 2.08 (m,1H), 1.79 (m, 1H). ¹³C NMR (DMSO-d₆): δ 175.3, 173.9, 170.5, 139.9,139.3, 138.1, 136.9, 133.5, 130.7, 129.0, 128.0, 127.8, 127.6, 127.0,116.7, 59.8, 54.0, 49.8, 44.1, 31.1, 29.6, 22.8.

Example 14 Synthesis ofN-(4-Methylbenzyl)-L-pyroglutamyl-L-(N′-benzyl)histidine Methyl Ester

The title compound was prepared from the appropriate starting materialsusing the procedures described in Examples 1 and 13.

NMR data was as follows:

¹H NMR (CDCl₃): δ 8.18 (d, 1H), 7.42 (s, 1H), 7.33 (m, 3H), 7.16-7.06(m, 6H), 6.67 (s, 1H), 5.14 (d, 1H), 5.04 (s, 2H), 4.79 (m, 1H), 3.88(m, 1H), 3.82 (d, 1H), 3.64 (s, 3H), 3.15-2.94 (m, 2H), 2.70-2.57 (m,1H), 2.39 (m, 1H), 2.27-2.00 (m, 2H). ¹³C NMR (CDCl₃): δ 176.2, 172.1,172.1, 138.3, 138.0, 137.9, 136.4, 133.5, 130.0, 129.6, 129.2, 120.0,127.8, 117.5, 60.8, 53.9, 53.9, 51.5, 45.5, 30.9, 29.5, 23.9, 21.7.

Example 15 Synthesis ofN-(4-Methylbenzyl)-L-pyroglutamyl-L-(N′-benzyl)histidine

The title compound was prepared from the product of Example 14 using theprocedures described in Method E.

NMR data was as follows:

¹H NMR (D₂O): δ 7.70 (s, 1H), 7.35-7.20 (m, 5H), 7.08 (d, 2H), 6.98 (s,1H), 6.74 (d, 2H), 5.05 (s, 2H), 4.49-4.42 (m, 2H), 3.94 (m, 1H), 3.31(d, 1H), 3.14-2.73 (m, 2H), 2.24 (s, 3H), 2.56-2.11 (m, 3H), 1.91 (m,1H).

Example 16 Synthesis of N-Benzyl-D-pyroglutamyl-L-phenylalanine

The title compound was prepared from the appropriate starting materialsusing the procedures described in Examples 1 and 2.

NMR data was as follows:

¹H NMR (DMSO-d₆): δ 8.52 (d, 1H), 7.4-7.1 (m, 10H), 6.97 (d, 1H), 4.83(dd, 2H), 4.73 (dd), 4.50 (m, 1H), 3.84 (m, 1H), 3.50 (dd, 2H), 3.40(dd), 3.13 (2H), 2.85 (2H), 2.19 (m, 2H), 2.03 (m, 1H), 1.48 (m, 1H).¹³C NMR (DMSO-d₆): δ 175.0, 173.2, 171.3, 138.0, 136.9, 129.5, 129.4,128.9, 128.9, 128.6, 128.4, 128.2, 127.7, 126.8, 57.1, 53.5, 44.5, 35.8,29.5, 22.9.

Example 17 Synthesis ofN-(4-Benzyl-3-oxothiomorpholin-5-carbonyl)-L-phenylalanine

The title compound was prepared from the product of Example 18 using theprocedure described in Method F.

NMR data was as follows:

¹H NMR (CDCl₃): δ 7.38-6.98 (m, 10H), 5.48 (d, 1H), 4.97 (m, 1H), 4.20(t, 1H), 4.09 (t), 3.67 (d, 1H), 3.50-2.78 (m, 6H). ¹³C NMR (CDCl₃): δ175.5, 169.7, 168.0, 136.2, 135.8, 129.9, 129.5, 129.3, 129.0, 128.7,128.0, 62.5, 53.9, 51.1, 38.0, 31.3, 29.4.

Example 18 Synthesis ofN-(4-Benzyl-3-oxothiomorpholin-5-carbonyl)-L-phenylalanine Ethyl Ester

Step A—Preparation of N-Benzyl-3-oxothiomorpholin-5-carboxylic Acid

S-(Methylcarboxyethyl)cysteine (Biochemistry, 1989, 28(2), 465) (1.633g, 7.88 mmol) was placed in MeOH (50 mL) and benzaldehyde (0.8 mL, 7.88mmol) was added. The mixture was stirred for 10 minutes and then sodiumcyanoborohydride (0.594 g, 946 mmol) was added. The reaction was stirredovernight under N₂ and then filtered to afford 853 mg of a white solid.This white solid was then heated in water overnight to affordN-benzyl-3-oxothiomorpholin-5-carboxylic acid as a white solid.

Step B—Preparation ofN-(4-Benzyl-3-oxothiomorpholin-5-carbonyl)-L-phenylalanine Ethyl Ester

The title compound was prepared from the product of Step A andL-phenylalanine ethyl ester using the procedures described in Method B.

NMR data was as follows:

¹H NMR (CDCl₃): δ 7.38-7.15 (m, 10H), 6.57 (d, 1H), 5.54 (d, 1H), 4.17(m, 1H), 4.89 (q, 1H), 4.20 (q, 2H), 3.09 (d, 1H) 3.46 (d, 1H),3.25-2.80 (m, 5H), 1.29 (t, 3H). ¹³C NMR (CDCl₃): δ 171.6, 169.4, 168.6,136.3, 136.1, 129.8, 129.7, 129.5, 129.3, 129.0, 128.6, 127.0, 62.4,62.4, 53.8, 50.7, 38.1, 31.3, 29.4, 14.8.

Example 19 Synthesis ofN-(4-Benzyl-3-oxothiomorpholin-5-carbonyl)-L-4-nitrophenylalanine MethylEster

The title compound was prepared from the appropriate starting materialsusing the procedures described in Example 18.

NMR data was as follows:

¹H NMR (CDCl₃): δ 8.16 (d, 2H), 7.42-7.17 (m, 7H), 6.84 (d, 1H), 5.63(d, 1H), 4.99 (m, 1H), 4.18 (m, 1H), 3.78-3.70 (m, 4H), 3.56 (d, 1H),3.38-3.15 (m, 3H), 3.05-2.87 (m, 2H). ¹³C NMR (CDCl₃): δ 171.5, 169.7,166.5, 147.8, 144.1, 136.1, 130.8, 129.5, 128.9, 128.8, 124.4, 62.5,53.7, 53.5, 50.9, 38.1, 31.5, 29.6.

Example 20 Synthesis ofN-Benzyl-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalanineIsopropyl Ester

The title compound was prepared from the appropriate starting materialsusing the procedure described in Method L to afford white crystals, mp167-169° C.

Physical data was as follows:

Anal. Calc'd for C₂₇H₃₃N₃O₆: C, 65.44; H, 6.71; N, 8.48. Found: C,65.06; H, 6.73; N, 8.42. MS (+EI): 495 (M+)+.

Example 21 Synthesis ofN-Benzyl-L-pyroglutamyl-L-3-chloro-4-(N,N-dimethylcarbamyloxy)phenylalanineMethyl Ester

N-Benzyl-L-pyroglutamyl-L-3-chloro-4-hydroxyphenylalanine methyl esterwas prepared from the appropriate starting materials using the proceduredescribed in Method B. The title compound was then prepared from themethyl ester using the procedure described in Method L to afford a whitesolid.

Physical data was as follows:

Anal. Calc'd for C₂₅H₂₈ClN₃O₆.0.1 CH₂Cl₂: C, 59.06; H, 5.57; N, 8.33.Found: C, 59.08; H, 5.37; N, 8.24. MS (+ESI): 502 (M+1)+.

Example 22 Synthesis ofN-(4-Fluorobenzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalanine

The title compound was prepared from the appropriate starting materialsusing the sequential application of the procedure described in MethodsB, L and N to afford a white solid, mp 227-230° C.

Physical data was as follows:

Anal. Calc'd for C₂₄H₂₆FN₃O₆: C, 61.14; H, 5.56; N, 8.91. Found: C,60.80; H, 5.48; N, 8.81. MS (+ESI): 472 (M+1)+.

Example 23 Synthesis ofN-(4-Fluorobenzyl)-L-pyroglutamyl-L-4-[(thiomorpholin-4′-yl)carbonyloxy)phenylalanine

N-(4-Fluorobenzyl)-L-pyroglutamyl-L-4-[(thiomorpholin-4′-yl)carbonyloxy)phenylalaninetert-butyl ester was prepared from the appropriate starting materialsusing the procedure described in Method M (thiomorpholine wassubstituted for N-methylpiperazine). The title compound was thenprepared from the tert-butyl ester using the procedure described inMethod N to afford a white solid, mp 266-268° C. (dec.)

Physical data was as follows:

Anal. Calc'd for C₂₆H₂₈FN₃O₆S: C, 58.97; H, 5.33; N, 7.93. Found: C,57.98; H, 5.09; N, 7.62. MS (−ESI): 528 (M−1)−.

Example 24 Synthesis ofN-(4-Cyanobenzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalanine

The title compound was prepared from the appropriate starting materialsusing the sequential application of the procedures described in MethodsB, L and N to afford a white solid, mp 232-236° C. (dec).

Physical data was as follows:

Anal. Calc'd for C₂₅H₂₆N₄O₆.0.5 H₂O.0.08 C₄H₁₀O: C, 61.63; H, 5.68; N,11.35. Found: C, 62.01; H, 5.51; N, 11.00. MS (+APCI): 479 (M+1)+.

Example 25 Synthesis ofN-(4-Nitrobenzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalaninetert-Butyl Ester

The title compound was prepared from the appropriate starting materialsusing the sequential application of the procedures described in MethodsB and L to afford white crystals, mp 159-161° C.

Physical data was as follows:

Anal. Calc'd for C₂₈H₃₄N₄O₈: C, 60.64; H, 6.18; N, 10.10. Found: C,60.41; H, 6.34; N, 9.73. MS (+ESI): 555 (M+1)+.

Example 26 Synthesis ofN-Benzyl-L-pyroglutamyl-L-3-chloro-4-(N,N-dimethylcarbamyloxy)phenylalanine

The title compound was prepared from the product of Example 21 using theprocedure described in Method D to afford a white solid.

Physical data was as follows:

Anal. Calc'd for C₂₄H₂ClN₃O₆Li.2.5 H₂O: C, 53.49; H, 5.61; N, 7.80.Found: C, 53.18; H, 5.02; N, 7.59. MS (+ESI): 488 (M+1)+.

Example 27 Synthesis ofN-(4-Fluorobenzyl)-L-pyroglutamyl-L-4-[(4′-(pyridin-2′-yl)piperazin-1′-yl)carbonyloxy]phenylalanine

The title compound was prepared from the product of Example 28 using theprocedure described in Method N.

Physical data was as follows:

Anal. Calc'd for C₃₁H₃₂FN₅O₆.2.5 HCO₂H: C, 60.47; H, 5.39; N, 11.02.Found: C, 57.31; H, 5.69; N, 9.53. MS (−ESI): 588 (M−1)−.

Example 28 Synthesis ofN-(4-Fluorobenzyl)-L-pyroglutamyl-L-4-[(4′-(pyridin-2′-yl)piperazin-1′-yl)carbonyloxy]phenylalaninetert-Butyl Ester

The title compound was prepared from the appropriate starting materialsusing the procedures of Method M (1-(pyridin-2-yl)piperazine wassubstituted for N-methylpiperazine) to afford white crystals, mp198-199° C.

Physical data was as follows:

Anal. Calc'd for C₃₅H₄₀FN₅O₆: C, 65.10; H, 6.24; N, 10.85. Found: C,65.04; H, 6.17; N, 10.77. MS (+ESI): 646 (M+1)+.

Example 29 Synthesis of N-(Pyridin-3-ylmethyl)-L-pyroglutamyl-L-tyrosinetert-Butyl Ester

Step A—Preparation of N-(Pyridin-3-ylmethyl)-L-pyroglutamic Acid MethylEster

N-(Pyridin-3-ylmethyl)-L-pyroglutamic acid methyl ester was prepared byreductive alkylation of L-glutamic acid with the appropriate aldehydefollowed by acid catalyzed cyclization employing the proceduresdescribed in J. Amer. Chem. Soc. 106, 4539 (1984). The following work-upprocedures were employed: after the aqueous solution (pH=3) was heatedovernight, the solution was cooled to 25° C. and the pH was adjusted to7 using 2N NaOH. The aqueous phase was lyophilized to a gummy solidwhich was treated with methanolic HCl overnight. After filtration, thesolvent was evaporated to afford the crude methyl ester which was takenup in CH₂Cl₂ and washed with saturated sodium bicarbonate, followed bysaturated brine, and then dried over MgSO₄ and evaporated to an oil.This oil was then flash chromatographed on alumina (activity grade 3)using ethyl acetate/hexane 1:1 as the eluent to affordN-(pyridin-3-ylmethyl)-L-pyroglutamic acid methyl ester as a colorlessoil.

Step B—Preparation of N-(Pyridin-3-ylmethyl)-L-pyroglutamyl-L-tyrosinetert-Butyl Ester

The title compound was prepared by reacting the acid obtained from thehydrolysis of the product of Step A (using Method D) and L-tyrosinetert-butyl ester following the procedures described in Method B.

Physical data was as follows:

Anal. Calc'd for C₂₄H₂₉N₃O₅.0.22 C₃H₇NO.0.7 H₂O: C, 63.26; H, 6.87; N,9.63. Found: C, 63.16; H, 6.60; N, 9.44. MS (+ESI): 440 (M+1)+.

Example 30 Synthesis ofN-(Pyridin-3-ylmethyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalanine

The title compound was prepared from the product of Example 31 using theprocedure described in Method N to afford a white solid.

Physical data was as follows:

Anal. Calc'd for C₂₃H₂₆N₄O₆.0.12 C₄H₈O₂.0.25 H₂O: C, 60.05; H, 5.89; N,11.93. Found: C, 59.94; H, 5.77; N, 11.91. MS (+ESI): 455 (M+1)+.

Example 31 Synthesis ofN-(Pyridin-3-ylmethyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamoyloxy)phenylalaninetert-Butyl Ester

The title compound was prepared from the product of Example 29 using theprocedure described in Method M to afford a crystalline solid, mp157-158° C.

Physical data was as follows:

Anal. Calc'd for C₂₇H₃₄N₄O₆: C, 63.51; H, 6.71; N, 10.97. Found: C,63.35; H, 6.75; N, 10.88. MS (+ESI): 511 (M+1)+.

Example 32 Synthesis ofN-(Pyridin-3-ylmethyl)-L-pyroglutamyl-L-4-[(4′-(pyridin-2′-yl)piperazin-1′-yl)carbonyloxy]phenylalaninetert-Butyl Ester

The title compound was prepared from the appropriate starting materialsusing the procedures of Method M (1-(pyridin-2-yl)piperazine wassubstituted for N-methylpiperazine) to afford a white solid.

Physical data was as follows:

Anal. Calc'd for C₃₄H₄₀N₆O₆: C, 64.95; H, 6.41; N, 13.37. Found: C,64.94; H, 6.40; N, 13.18. MS (+ESI): 629 (M+1)+.

Example 33 Synthesis ofN-(Pyridin-3-ylmethyl)-L-pyroglutamyl-L-4-[(4′-(pyridin-2′-yl)piperazin-1′-yl)carbonyloxy]phenylalanine

The title compound was prepared from the product of Example 32 using theprocedure described in Method N to afford a white solid.

Physical data was as follows:

Anal. Calc'd for C₃₀H₃₂N₆O₆: C, 62.93; H, 5.63; N, 14.68. Found: C,62.20; H, 5.49; N, 14.22. MS (−ESI): 571 (M−1)−.

Example 34 Synthesis of N-(4-Benzyl-5-oxo-4-azatricyclo[4.2.1.0(3,7)]nonane-3-carbonyl)-L-tyrosine tert-Butyl Ester

Step A—Preparation of 5-Oxo-4-azatricyclo[4.2.1.0(3,7)]nonane-3-carboxylic Acid

A solution of endo-6-carboxybicyclo[2.2.1]heptane-2-one (6.72 g, 43.6mmol (J. Org. Chem. 41:1233 (1976)), KCN (3.41 g, 52.4 mmol) and(NH₄)₂CO₃ (16.77 g, 174.6 mmol) in 206 mL 1:1 H₂O-ethanol was heated 24h at 55° C. The condenser was then removed and the reaction mixture wasrefluxed for 1.5 h. After the reaction was acidified with conc. HCl andcooled to 5° C., a precipitate was obtained which after washing with H₂Oand dried to afford 1.74 g (18%) of a white solid, mp 286° C. Thisintermediate (1.74 g, 7.76 mmol) was converted to the title compound byrefluxing in 30 mL of 2.5 N NaOH for 24 h. Acidification to pH=0 gavethe desired product as a white solid, mp 298-300° C.

Physical data was as follows:

Anal. Calc'd for C₉H₁₁NO₃: C, 59.66; H, 6.12; N, 7.73. Found: C, 59.39;H, 6.24; N, 7.67.

Step B—Preparation of 5-Oxo-4-azatricyclo[4.2.1.0(3,7)]nonane-3-carboxylic Acid Methyl Ester

To a suspension of 5-oxo-4-azatricyclo[4.2.1.0 (3,7)]nonane-3-carboxylicacid (183 mg, 1.0 mmol) in 10 mL MeOH under nitrogen at −78° C. wasadded SOCl₂ (75 μL, 1.0 mmol). After 169 h, the solvent was evaporatedto afford 195 mg of a white solid which was taken up in 10 ML CHCl₃,washed sequentially with 10 mL saturated NaHCO₃ and 10 mL saturatedNaCl, dried over MgSO₄ and evaporated to give 160 mg (81%) of a whitesolid, mp 142-144° C.

Physical data was as follows:

MS (FI-POS): 196 (M+1)+.

Step C—Preparation of 4-Benzyl-5-oxo-4-azatricyclo[4.2.1.0(3,7)]nonane-3-carboxylic Acid Methyl Ester

To a suspension of 5-oxo-4-azatricyclo[4.2.1.0 (3,7)]nonane-3-carboxylicacid methyl ester (688 mg, 3.52 mmol) in 10 mL of THF under nitrogen at25° C. was added LiHMDS (3.87 mL of 1N THF solution, 3.87 mmol). After15 min, benzyl bromide (0.42 mL, 3.53 mmol) was added. After 169 h, thereaction was quenched by addition of 10 mL of saturated NH₄Cl solution.The reaction mixture was partitioned between 30 mL CH₂Cl₂ and 10 mL H₂O.The organic phase was separated, washed with 50 mL saturated NaCl, driedover MgSO₄ and evaporated to give 770 mg of an oil. Flash chromatographyof 740 mg of this material, eluting with 95:5 CH₂CH₂-EtOAc, afforded 510mg (51%) of the title compound as a colorless oil (0.14 CH₂Cl₂ solvate).

Physical data was as follows: MS (+ESI): 286 (M+1)+.

Step D—Preparation of 4-Benzyl-5-oxo-4-azatricyclo[4.2.1.0(3,7)]nonane-3-carboxylic Acid

To a solution of 4-benzyl-5-oxo-4-azatricyclo[4.2.1.0(3,7)]nonane-3-carboxylic acid methyl ester.0.14 methylene chloridesolvate (399 mg, 1.34 mmol) in 13 mL MeOH under nitrogen at 25° C. wasadded 1.5 mL of 1N LiOH. After 117 h, most of the solvent was removedand the residue was taken up in 10 mL 1N NaOH, washed with 2×10 mL Et₂O,acidified by addition of 10 mL 2 N HCl, extracted 2× with 10 mL Et₂O,dried over MgSO₄ and evaporated to give 225 mg (71%) of a white solid,mp 191-194° C.

Physical data was as follows:

Anal. Calc'd for C₁₆H₁₇NO₃: C, 70.83; H, 6.32; N, 5.16. Found: C, 70.56;H, 6.39; N, 5.01.

Step E—Preparation of N-(4-Benzyl-5-oxo-4-azatricyclo[4.2.1.0(3,7)]nonane-3-carbonyl)-L-tyrosine tert-Butyl Ester

The title compound was prepared from4-benzyl-5-oxo-4-azatricyclo[4.2.1.0 (3,7)]nonane-3-carboxylic acid(0.60 mmol) and L-tyosine tert-butyl ester using the proceduresdescribed in Example 1 to afford 300 mg (93%) of a white solid.

Physical data was as follows:

Anal. Calc'd for C₂₉H₃₄N₂O₅.0.5 C₄H₈O₂: C, 69.64; H, 7.16; N, 5.24.Found: C, 69.41; H, 7.02; N, 5.34. MS (+ESI): 491 (M+1)+.

Example 35 Synthesis of N-(4-Benzyl-5-oxo-4-azatricyclo[4.2.1.0(3,7)]nonane-3-carbonyl)-L-4-(N,N-dimethylcarbamyloxy)phenylalaninetert-Butyl Ester

The title compound was prepared from the product of Example 34 using theprocedure described in Method L to afford a white solid.

Physical data was as follows:

Anal. Calc'd for C₃₂H₃₉N₃O₆: C, 68.43; H, 7.00; N, 7.48. Found: C,67.98; H, 7.00; N, 7.27. MS (+ESI): 562 (M+1)+.

Example 36 Synthesis of N-(4-Benzyl-5-oxo-4-azatricyclo[4.2.1.0(3,7)]nonane-3-carbonyl)-L-4-(N,N-dimethylcarbamyloxy)phenylalanine

The title compound was prepared from the product of Example 35 using theprocedure described in Method N to afford a white solid.

Physical data was as follows:

Anal. Calc'd for C₂₈H₃₁N₃O₆.0.5 C₄H₁₀O: C, 66.40; H, 6.69; N, 7.74.Found: C, 65.72; H, 6.42; N, 7.95. MS (+ESI): 506 (M+1)+.

Example 37 Synthesis of N-(Benzyl)-L-pyroglutamyl-L-tyrosine Ethyl Ester

To a solution of N-benzyl-L-pyroglutamic acid (J. Am. Chem. Soc.106:4539 (1984), 1.00 g, 4.56 mmol), L-tyrosine ethyl esterhydrochloride (1.23 g, 5.01 mmol) and BOP (2.22 g, 5.01 mmol) in DMF (32mL) under nitrogen was added triethylamine (1.14 g, 11.26 mmol) dropwiseand the resulting solution was stirred at ambient temperature for 22.5h. The reaction was quenched by addition of 150 mL of saturated sodiumbicarbonate and 150 mL of EtOAc. The organic layer was separated andwashed sequentially with 150 mL H₂O, 150 mL 10% citric acid and 150 mLsaturated brine, dried over MgSO₄ and evaporated to 1.6 g (82%) of awhite solid, mp 192-194° C.

Physical data was as follows:

¹H NMR (DMSO-d₆, 400 MHz) δ 9.23 (s, 1H); 8.52 (d, 1H, J=7.9 Hz);7.32-7.23 (m, 3H); 7.03-6.97 (m, 4H); 6.69-6.65 (m, 2H); 4.75 (d, 1H,J=15.2 Hz); 4.49-4.43 (m, 1H); 4.11-4.01 (m, 2H); 3.88-3.85 (m, 1H);3.37 (d, 1H, J=15.2 Hz); 2.99-2.94 (m, 1H); 2.78-2.72 (m, 1H); 2.33-2.08(m, 3H); 1.98 (s, 0.2H); 1.76-1.70 (m, 1H); 1.14 (t, 3H, J=7.25 Hz). IR(KBr, cm⁻¹) 3400; 3250; 3060; 1725; 1680; 1670; 1550; 1510; 1440; 1265;1220. MS (−FAB) 409.1 (M−H); 381.0; 302.0; 275.0; 257.0; 217.0; 183.0;91.0. Anal. Calc'd for C₂₃H₂₆N₂O₅.0.2M EtOAc: C, 66.78; H, 6.50; N,6.54. Found: C, 66.48; H, 6.35; N, 6.66.

Example 38 Synthesis of N-(Benzyl)-L-pyroglutamyl-L-tyrosine

To a solution of N-(benzyl)-L-pyroglutamyl-L-tyrosine ethyl ester 0.2ethyl acetate solvate (0.139 g, 0.325 mmol) in MeOH (3.25 mL) undernitrogen was added 1 N aqueous LiOH (0.72 mL, 0.72 mmol). After 3 days,the solvent was evaporated and the residue was partitioned between 10 mLH₂O and 10 mL CH₂Cl₂. The aqueous layer was washed with 10 mL CH₂Cl₂ andacidified to pH=1 by addition of 7 mL 1 N HCl. The precipitate wasfiltered, washed with 20 mL 1:1 CHCl₃/EtOAc and dried to afford 0.0835 gof a white solid (67%).

Physical data was as follows:

¹H NMR (DMSO-d₆, 400 MHz) δ 12.76 (brd s, 1H); 9.22 (s, 1H); 8.40 (d,1H, J=8.35 Hz); 7.32-7.23 (m, 3H); 7.02-6.97 (m, 4H); 6.68-6.65 (m, 2H);4.74 (d, 1H, J=14.94 Hz); 4.47-4.41 (m, 1H); 3.87-3.84 (m, 1H);3.40-3.24 (m, 1H); 3.03-2.98 (m, 1H); 2.75-2.69 (m, 1H); 2.35-2.04 (m,3H); 1.76-1.69 (m, 1H). IR (KBr, cm⁻¹) 3280; 1745; 1670; 1660; 1550;1515; 1255; 1200; 820; 700. MS (+FAB) 383.1 (M+H); 367.1; 327.0; 311.0;295.0; 279.0; 237.0; 197.0; 174.1; 136.0; 105.0. Anal. Calc'd forC₂₁H₂₂N₂O₅.0.2M H₂O: C, 65.35; H, 5.85; N, 7.26. Found: C, 65.14; H,5.66; N, 7.13.

Example 39 Synthesis ofN-(Benzyl)-L-pyroglutamyl-L-4-[(4′-methylpiperazin-1′-yl)carbonyloxy]phenylalanineEthyl Ester

To a suspension of N-(benzyl-L-pyroglutamyl)-L-tyrosine ethyl ester 0.2ethyl acetate solvate (0.894 g, 2.09 mmol) and 4-nitrophenylchloroformate (0.435 g, 2.09 mmol) in 13 mL of 1:1 CH₃CN/CH₂Cl₂ undernitrogen at 0° C. was added DMAP (0.032 g, 0.26 mmol) followed by TEA(0.529 g, 5.22 mmol). After 30 min at 0° C. the reaction mixture waswarmed up to 25° C. and kept at this temperature for 30 min. Thereaction was then cooled back down to 0° C. and 1-methylpiperazine(0.206 g, 1.06 mmol) was added. The ice bath was then removed and thereaction mixture was stirred at 25° C. for 3 h 15 min. The reactionmixture was then diluted with 50 mL Et₂O and washed with 4×25 mL 10%sodium carbonate, diluted with CH₂Cl₂, dried over K₂CO₃ and evaporatedto 1.0 g (88%) of crude solid which was recrystallized fromtoluene/hexane to afford white crystals, mp 145-148° C.

Physical data was as follows:

¹H NMR (DMSO-d₆, 400 MHz) δ 8.59 (d, 1H, J=8.1 Hz); 7.31-7.19 (m, 5H);7.04-7.00 (m, 4H); 4.76 (d, 1H, J=15.2 Hz); 4.56-4.51 (m, 1H); 4.11-4.05(m, 2H); 3.87-3.84 (m, 1H); ); 3.54-3.35 (m, 5H); 3.10-3.05 (m, 1H);2.90-2.84 (m, 1H); 2.32-2.09 (m, 10H); 1.74-1.69 (m, 1H); 1.24-1.23 (m,0.4H); 1.15 (t, 3H, J=7.0 Hz); 0.85 (m, 0.3H). IR (KBr, cm⁻¹) 3300;1740; 1720; 1680; 1650; 1550; 1410; 1240; 1210; 1200; 1160; 700. MS (EI)536 (M+); 491; 234; 174; 127; 91; 83; 70; 58; 44. Anal. Calc'd forC₂₉H₃₆N₄O₆.0.1M C₆H₁₄: C, 65.22; H, 6.90; N, 10.28. Found: C, 65.06; H,6.66; N, 9.88.

Example 40 Synthesis ofN-(Benzyl)-L-pyroglutamyl-L-4-(1′-methylpiperidin-4′-yloxy)phenylalanineLithium Salt

To a solution ofN-(benzyl)-L-pyroglutamyl-L-4-[(4′-methylpiperazin-1′-yl)carbonyloxy]phenylalanineethyl ester 0.1 hexane solvate (0.200 g, 0.367 mmol) in MeOH (3.67 mL)under nitrogen was added 1 N aqueous LiOH (0.35 mL, 0.35 mmol). After 28h the solvent was removed, 25 mL H₂O was added, the aqueous solution waswashed twice with 25 mL of CH₂Cl₂, filtered and lyophilized to afford0.16 g (77%) of a white solid.

Physical data was as follows:

¹H NMR (DMSO-d₆, 400 MHz) δ 7.60 (d, 2H, J=7.3 Hz); 7.30-7.21 (m, 3H);7.13-7.10 (m, 2H); 7.05-7.03 (m, 2H); 6.92-6.88 (m, 2H); 4.75 (d, 1H,J=15.2 Hz); 4.04-4.01 (m, 1H); 3.89-3.86 (m, 1H); 3.54-3.33 (m, 1H);3.13-3.09 (m, 1H); 2.92-2.87 (m, 1H); 2.33-2.05 (m, 10H); 1.79-1.75 (m,1H). IR (KBr, cm⁻¹) 3400; 1720; 1680; 1610; 1420; 1240; 1200; 1160;1000; 710. MS (+FAB) 515.0 (M+Li); 471.0; 220.9; 174.0; 91.0. Anal.Calc'd for C₂₇H₃₁N₄O₆Li.3.0M H₂O: C, 57.04; H, 6.56; N, 9.85. Found: C,57.27; H, 5.70; N, 9.59.

Example 41 Synthesis ofN-(Benzyl)-L-pyroglutamyl-L-4-(pyridin-4-ylcarbonylamino)phenylalanineMethyl Ester

A solution of N-benzyl-L-pyroglutamic acid (J.Am.Chem.Soc. 106:4539(1984), 1.00 g, 4.562 mmol),4-[(4-pyridinylcarbonyl)amino]-L-phenylalanine methyl ester (1.532 g,4.562 mmol) and BOP (2.018 g, 4.562 mmol) in acetonitrile (30.0 mL) wascharged to a 100 mL round bottom flask equipped with a stir bar andnitrogen inlet. Triethylamine (1.272 mL, 9.123 mmol) was added dropwiseand the resulting solution was stirred at 25° C. for 16 h. The solventwas stripped off and the material taken up in methylene chloride (75 mL)and washed with saturated sodium bicarbonate solution (50 mL×3), dried(K₂CO₃) and the solvent removed to give a biege solid (2.000 g). Thismaterial was chromatographed on silica gel (9:1 CH₂Cl₂:CH₃OH) yielding awhite solid which was recrystallized from acetonitrile to provide 1.744g (76%) of white needles, mp=204-208° C.

Physical data was as follows:

¹H NMR (DMSO-d₆, 400 MHz) δ 10.47 (s, 1H); 8.77 (d, 2H, J=6.2 Hz); 8.60(d, 1H, J=7.9 Hz); 7.83 (d, 2H, J=6.2 Hz); 7.71 (d, 2H, J=8.6 Hz);7.31-7.19 (m, 5H); 7.02 (d, 2H, J=5.1 Hz); 4.76 (d, 1H, J=14.9 Hz);4.61-4.55 (m, 1H); 3.87-3.84 (m, 1H); 3.65 (s, 3H); 3.36 (d, 1H, J=14.4Hz); 3.11-3.06 (m, 1H); 2.89-2.83 (m, 1H); 2.34-2.21 (m, 2H); 2.17-2.09(m, 1H); 1.76-1.70 (m, 1H). IR (KBr, cm⁻¹) 3400; 3325; 3100; 3030; 2960;1660; 1625; 1540; 1490; 1425; 1325; 1225; 700. MS (+FAB) 501.1 (M+H);485.1; 475.1; 465.1; 451.0; 394.1; 279.0; 174.0; 91.0. Anal. Calc'd forC₂₈H₂₈N₄O₅.0.15 CH₂Cl₂: C, 65.87; H, 5.56; N, 10.92. Found: C, 65.87; H,5.70; N, 11.36.

Example 42 Synthesis ofN-(Benzyl)-L-pyroglutamyl-L-4-(pyridin-4-ylcarbonylamino)phenylalanineLithium Salt

N-(Benzyl)-L-pyroglutamyl-L-4-(pyridin-4-ylcarbonylamino)-phenylalaninemethyl ester 0.15 methylene chloride solvate (0.400 g, 0.799 mmol) wastaken up in methanol (15 mL) and the solvent stripped off using arotovap. This procedure was repeated twice more to remove any traces ofacetonitrile. The solid was dissolved in methanol (15 mL) and charged toa 25 mL round bottom flask equipped with a magnetic stir bar, aircondenser and nitrogen inlet. The mixture was warmed until the esterdissolved (oil bath temperature=40° C.) and 1N LiOH (759 μL, 0.759 mmol)was added, via syringe, and the solution stirred for 16 h undernitrogen. The reaction solution was transferred to a 50 mL round bottomflask and the solvent stripped off yielding a white solid (0.731 g).This solid was taken up in water (50 mL) and washed with methylenechloride (25 mL). An emulsion formed and was allowed to separate. Theorganic phase was separated and the aqueous phase was filtered, pumpedon for 3 h and lyophilized to give 0.353 g (94%) of a fluffy whitesolid, mp=347° C. (decompose).

Physical data was as follows:

¹H NMR (DMSO-d₆, 400 MHz) δ 10.48 (s, 1H); 8.76-8.74 (m, 2H); 7.85-7.83(m, 2H); 7.60 (t, 2H, J=8.6 Hz); 7.53 (d, 1H, J=6.8 Hz); 7.30-7.20 (m,3H); 7.15-7.09 (m, 2H); 7.04 (d, 2H, J=7.6 Hz); 4.77 (d, 1H, J=15.4 Hz);4.01-3.98 (m, 1H); 3.90-3.86 (m, 1H); 3.43 (d, 1H, J=15.2 Hz); 3.13-3.08(m, 1H); 2.94-2.89 (m, 1H); 2.29-2.19 (m, 2H); 2.11-2.05 (m, 1H);1.80-1.77 (m, 1H). IR (KBr, cm⁻¹) 3325; 3030; 2960; 1660; 1600; 1530;1425; 1325; 830; 700. MS (+FAB) 487.0 (M+H); 471.0; 450.9; 429.0; 417.0;400.9; 385.0; 279.0; 236.9; 91.0. Anal. Calc'd for C₂₇H₂₆N₄O₅.3.00 H₂OC, 58.34; H, 5.72; N, 10.25. Found: C, 58.45; H, 5.44; N, 9.95.

Example 43 Synthesis of N-(Benzyl)-L-pyroglutamyl-L-4-nitrophenylalanineEthyl Ester

A solution of N-benzyl-L-pyroglutamic acid (J. Am. Chem. Soc. 106:4539(1984), 1.00 g, 4.562 mmol), (S)-4-nitro-phenylalanine ethyl ester(1.262 g, 4.562 mmol) and HOBT (1.233 g, 9.123 mmol) in methylenechloride (40.0 mL) was charged to a 100 mL round bottom flask equippedwith a stir bar and nitrogen inlet. Hunig's base (3.25 mL, 18.246 mmol)was added dropwise. The solution remained heterogeneous so acetonitrile(10 mL) was added followed by the addition of EDC (1.749 g, 9.123 mmol)and the resulting milk white mixture was stirred at 25° C. for 16 h. Thesolvent was stripped off and the solid taken up in ethyl acetate (100mL) and washed with saturated ammonium chloride solution (100 mL×2),saturated sodium bicarbonate solution (50 mL×2), brine (50 mL×2), dried(MgSO₄) and the solvent removed to yield 1.166 g (58%) of a yellowsolid. This material was recrystallized from ethyl acetate giving awhite solid, mp=186-187° C.

Physical data was as follows:

¹H NMR (DMSO-d₆, 400 MHz) δ 8.63 (d, 1H, J=8.1 Hz); 8.15 (d, 2H, J=9.1Hz); 7.51 (d, 2H, J=8.8 Hz); 7.29-7.23 (m, 3H); 6.99-6.95 (m, 2H); 4.76(d, 1H, J=15.2 Hz); 4.69-4.64 (m, 1H); 4.11 (q, 2H, J=5.5 Hz); 3.82-3.79(m, 2H); 3.37 (d, 1H, J=15.2 Hz); 3.28-3.23 (m, 1H); 3.06-3.00 (m, 1H);2.33-2.21 (m, 2H); 2.17-2.09 (m, 1H); 1.73-1.65 (m, 1H); 1.16 (t, 3H,J=7.1 Hz). IR (KBr, cm⁻¹) 3300; 3100; 2990; 2900; 1730; 1690; 1600;1515; 1450; 1350; 1275; 1250; 1175; 1100; 1025; 840; 750; 700. MS (+FAB)439.0 (M+H); 422.0; 394.0; 366.0; 176.0; 175.0; 174.0; 165.0; 146.0;118.0; 106.0; 92.0; 91.0; 90.0; 84.0; 65.0. Anal. Calc'd forC₂₄H₂₆N₂O₆.0.09 CH₂Cl₂C, 62.03; H, 5.80; N, 9.59. Found: C, 62.03; H,5.68; N, 9.40.

Example 44 Synthesis of N-(Benzyl)-L-pyroglutamyl-L-4-nitrophenylalanineLithium Salt

N-(Benzyl)-L-pyroglutamyl-L-4-nitrophenylalanine ethyl ester 0.09methylene chloride solvate (0.100 g, 0.228 mmol) was dissolved inrefluxing ethanol (10 mL) and charged to a 25 mL round bottom flaskequipped with a magnetic stir bar, air condenser and nitrogen inlet. 1NLiOH (216 μL, 0.216 mmol) was added, via syringe, and the solutionstirred at 70° C. for 16 h under nitrogen. The reaction solution wentfrom clear to brown upon the LiOH addition and some precipitate wasnoted. This solution was transferred to a 125 mL separatory funnel withan additional 50 mL of water and washed with methylene chloride (50 mL).An emulsion formed and was allowed to separate. The organic phase wasremoved and the aqueous phase was filtered, pumped on for 3 h andlyophilized to give 0.048 g, (53%) of a fluffy white solid, mp=285-287°C. (decompose).

Physical data was as follows:

¹H NMR (DMSO-d₆, 400 MHz) δ 8.07-8.02 (m, 2H); 7.64-7.61 (m, 1H);7.39-7.36 (m, 2H); 7.31-7.21 (m, 3H); 7.13 (d, 1H, J=7.5 Hz); 7.00 (d,1H, J=7.6 Hz); 4.75 (d, 1H, J=15.4 Hz); 4.06-4.01 (m, 1H); 3.94-3.89 (m,1H); 3.45 (d, 1H, J=15.4 Hz); 3.07-2.99 (m, 1H); 2.29-2.14 (m, 2H);2.12-2.00 (m, 1H); 1.79-1.73 (m, 1H); 1.57-1.54 (m, 1H). IR (KBr, cm³¹¹) 3400; 3100; 2900; 1675; 1600; 1515; 1450; 1425; 1350; 1250; 1100;840; 690. MS (−FAB) 410.1 (M−H); 394.0; 337.1; 275.1; 217.1; 183.0;153.0; 109.0; 91.0. Anal. Calc'd for C₂₁H₂₁N₃O₆.1.25 H₂OC, 57.34; H,5.16; N, 9.55. Found: C, 57.44; H, 5.05; N, 9.48.

Example 45 Synthesis of N-(Benzyl)-L-pyroglutamyl-L-4-aminophenylalanineEthyl Ester

A solution of N-(benzyl)-L-pyroglutamyl-L-4-nitrophenylalanine ethylester 0.09 methylene chloride solvate (0.900 g, 2.048 mmol) andSnCl₂.H₂O in ethanol (30 mL) was charged to a 100 mL round bottom flaskequipped with a magnetic stir bar and nitrogen inlet. This solution wasstirred at ambient temperature, under nitrogen, for 16 h. The reactionsolution was transferred to a 125 mL separatory funnel with 50 mL ofethyl acetate. The organic phase was washed with saturated sodiumbicarbonate (50 mL), dried (K₂CO₃), and the solvent removed to yield0.702 g of a white solid. This material was chromatographed on silicagel (ethyl acetate) giving 0.362 g (39%) of a white solid, mp=147-149°C.

Physical data was as follows:

¹H NMR (DMSO-d₆, 400 MHz) δ 8.49 (d, 1H, J=8.1 Hz); 7.34-7.24 (m, 3H);7.04 (d, 2H, J=7.7 Hz); 6.84 (d, 2H, J=8.3 Hz); 6.48 (d, 2H, J=9.3 Hz);4.94 (s, 2H); 4.76 (d, 1H, J=14.9 Hz); 4.44-4.38 (m, 1H); 4.11-4.01 (m,2H); 3.89-3.86 (m, 1H); 3.40 (d, 1H, J=15.2 Hz); 2.91-2.86 (m, 1H);2.72-2.66 (m, 1H); 2.34-2.20 (m, 2H); 2.16-2.08 (m, 1H); 1.77-1.71 (m,1H); 1.16 (t, 3H, J=7.1 Hz).

IR (KBr, cm⁻¹) 3400; 3300; 3040; 3030; 2990; 2950; 1740; 1675; 1550;1525; 1425; 1225; 1200; 1125; 830; 700. MS (+FAB) 409.0 (M+H); 336.0;254.0; 253.0; 191.0; 174.0; 146.0; 107.0; 106.0; 91.0; 90.0; 77.0; 65.0;55.0; 46.0; 45.0; 44.0. Anal. Calc'd for C₂₃H₂₇N₃O₄: C, 67.47; H, 6.65;N, 10.26. Found: C, 67.08; H, 6.69; N, 10.20.

Example 46 Synthesis ofN-(Benzyl)-L-pyroglutamyl-L-4-[(thiomorpholin-4′-yl)carbonyloxy]phenylalaninetert-Butyl Ester

A solution of N-benzyl-L-pyroglutamic acid (J. Am. Chem. Soc. 106:4539(1984), 10.00 g, 45.62 mmol), L-tyrosine tert-butyl ester (11.91 g,50.17 mmol) and BOP (22.19 g, 50.17 mmol) in DMF (250.0 mL) was chargedto a 500 mL round bottom flask equipped with a stir bar and nitrogeninlet. Triethylamine (7.00 mL, 50.17 mmol) was added dropwise and theresulting solution was stirred at 25° C. for 16 h. The solution wastransferred to a 1.0 L separatory funnel with ethyl acetate (300 mL) andwashed with saturated sodium bicarbonate solution (300 mL×2), brine (300mL×2), dried (MgSO₄) and the solvent removed to give 18.63 g (93%) ofN-(benzyl)-L-pyroglutamyl-L-tyrosine tert-butyl ester as a white solid.

A solution of N-(benzyl)-L-pyroglutamyl-L-tyrosine tert-butyl ester(1.00 g, 2.280 mmol) and 4-nitrophenyl chloroformate (0.442 g, 2.092mmol) were dissolved in methylene chloride (5 mL) and charged to a 25 mLround bottom flask equipped with a magnetic stir bar and nitrogen inlet.The solution was cooled in an ice bath and triethylamine (729 μL, 5.230mmol) was added, via syringe, and the resulting yellow solution wasstirred for 30 min in an ice bath, then 30 min at ambient temperature.The solution was recooled in an ice bath and thiomorpholine (210 μL,2.092 mmol) was added. The solution was allowed to warm to roomtemperature and stirred for 16 h under nitrogen. The solution wastransferred to a 250 mL separatory funnel with 100 mL of diethyl etherand this organic phase was washed with 10% K₂CO₃ (50 mL×12), dried(K₂CO₃) and the solvent removed to give a white solid (0.992 g). Thismaterial was recrystallized from ethanol to yield 0.411 g (35%) of whitecrystals, mp=169-171° C.

Physcial data was as follows:

¹H NMR (DMSO-d₆, 400 MHz) δ 8.53 (d, 1H, J=8.1 Hz); 7.33-7.21 (m, 5H);7.07-7.03 (m, 4H); 4.78 (d, 1H, J=15.2 Hz); 4.49-4.36 (m, 1H); 3.89-3.86(m, 1H); 3.82 (s, 2H); 3.68 (s, 2H); 3.43 (d, 1H, J=17.0 Hz); 3.08-3.03(m, 1H); 2.89-2.83 (m, 1H); 2.67 (s, 4H); 2.32-2.26 (m, 2H); 2.17-2.11(m, 1H); 1.77-1.73 (m, 1H); 1.38 (s, 9H). IR (KBr, cm⁻¹) 3400; 3300;3100; 2980; 2910; 1725; 1675; 1660; 1560; 1510; 1460; 1420; 1375; 1300;1225; 1200; 1100; 960; 800; 760; 700; 650; 550. MS (+FAB) 635.5 (M+NH₄);618.4; 562.2; 506.4; 407.8; 344.5; 255.9.

Example 47 Synthesis ofN-(Benzyl)-L-pyroglutamyl-L-4-(1′-benzyloxycarbonylpiperidin-4′-ylcarbonylamino)phenylalanineMethyl Ester

To a solution of N-benzyl-L-pyroglutamic acid (0.50 g, 2.275 mmol),L-4-(1′-benzyloxycarbonylpiperidin-4′-ylcarbonylamino)phenylalaninemethyl ester hydrochloride (1.08 g, 2.275 mmol) and BOP (1.10 g, 2.48mmol) in acetonitrile (60 mL) under nitrogen was added triethylamine(0.7 mL, 5.005 mmol) dropwise. The mixture was stirred 48 h at roomtemperature. The reaction was then worked-up by evaporation of thesolvent, addition of ethyl acetate, sequential washing with 1N HClsolution, water, saturated sodium bicarbonate solution, saturated brineand drying with MgSO₄. Evaporation of the solvent gave a crude solidwhich was purified by flash chromatography using EtOAc/MeOH (99:1) aseluent, to afford the desired product as a solid (0.332 g, mp 223-225°C., 23% yield).

Physical data was as follows:

¹H NMR (DMSO-d₆, 400 MHz) δ 9.88 (s, 1H); 8.56 (d, 1H, J=8.1 Hz); 7.52(d, 2H, J=8.5 Hz); 7.4-7.2 (m, 8H); 7.11 (d, 2H, J=8.3 Hz); 6.99 (d, 2H,J=8.1 Hz); 5.07 (s, 2H); 4.73 (d, 1H, J=14.7 Hz); 4.54 (m, 1H); 4.02 (m,2H); 3.84 (m, 1H); 3.63 (s, 3H); 3.27 (m, 2H); 3.02 (m, 1H); 2.90-2.79(brd m, 3H); 2.30-2.23 (brd m, 2H); 2.10 (m, 1H); 1.80-1.70 (brd m, 3H);1.55-1.45 (brd m, 2H). IR (KBr, cm⁻¹) 3400; 3275; 2910; 1690; 1550;1435; 1325; 1225; 1120; 1100; 1010; 940; 700. MS (+FAB) 663.1 ([M+Na]⁺);597.1; 507.1; 174.0; 91.0. Anal. Calc'd for C₃₆H₄₀N₄O₇.0.15C₄H₈O₂: C,66.12; H, 6.35; N, 8.56. Found: C, 66.03; H, 5.01; N, 8.56.

Example 48 Synthesis ofN-(Benzyl)-L-pyroglutamyl-L-4-(1′-benzyloxycarbonylpiperidin-4′-ylcarbonylamino)phenylalanine

To a suspension ofN-(benzyl)-L-pyroglutamyl-L-4-(1′-benzyloxycarbonyl-piperidin-4′-ylcarbonylamino)phenylalaninemethyl ester (0.30 g, 0.468 mmol) in a aqueous methanol solution(MeOH/H₂O, 12 mL/1 mL) under nitrogen was added solid LiOH (0.039 g,0.929 mmol). After stirring for 24 h, the solvent was concentrated toabout 3mL and acidified using 10% citric acid solution. A whiteprecipitate was filtered off, washed with water and dried in vacuo toyield the product as a off white solid (0.22 g, mp 193-196° C., yield75%).

Physical data was as follows:

¹H NMR (DMSO-d₆, 400 MHz) δ 9.87 (s, 1H); 8.42 (d, 1H, J=8.3 Hz); 7.52(d, 2H, J=8.5 Hz); 7.4-7.2 (m, 8H); 7.11 (d, 2H, J=8.5 Hz); 6.97 (d, 2H,J=7.9 Hz); 5.07 (s, 2H); 4.73 (d, 1H, J=15.1 Hz); 4.49 (m, 1H); 4.02(brd d, 2H, J=12.7 Hz); 3.84 (m, 1H); 3.26 (s, 1H); 3.07 (m, 1H);2.98-2.7 (brd m, 3H); 2.32-2.20 (brd m, 2H); 2.10 (m, 1H); 1.80-1.70(brd m, 3H); 1.55-1.45 (brd m, 2H).

IR (KBr, cm⁻¹) 3420; 3300; 3050; 2950; 1660; 1550; 1440; 1325; 1225;1175; 1110; 1060; 950; 820; 760; 700; 510. MS (−FAB) 625.4 ([M−H]−);491.3; 367.2; 275.1; 183.1; 91.0. Anal. Calc'd for C₃₅H₃₈N₄O₇.1.5 H₂O:C, 64.30; H, 6.32; N, 8.57. Found: C, 64.33; H, 6.09; N, 8.44.

Example 49 Synthesis ofN-(Benzyl)-L-pyroglutamyl-L-4-(piperidin-4′-ylcarbonylamino)phenylalanineHydrobromide

Hydrogen bromide in HOAc (33 wt. %, 2 mL) was added to a flaskcontainingN-(benzyl)-L-pyroglutamyl-L-4-(1′-benzyloxycarbonylpiperidin-4′-ylcarbonylamino)phenylalanine(0.10 g, 0.16 mmol) and stirred for 50 min. Et₂O was added until aprecipitate fell out of solution and the mixture was then stirred for 10min. The precipitate was filtered off and washed with fresh Et₂O. TheEt₂O layers were discarded. The precipitate was then washed with wateruntil all of the material on the filter paper dissolved. This aqueousphase was then lyophilized to generate the product as a solid (0.082 g,mp 191-194° C., 81% yield).

Physical data was as follows:

¹H NMR (DMSO-d₆, 400 MHz) δ 9.98 (s, 1H); 8.48 (m, 2H); 8.25 (brd s,1H); 7.52 (d, 2H, J=8.3 Hz); 7.27-7.20 (m, 3H); 7.13 (d, 2H, J=8.5 Hz);6.97 (d, 2H, J=8.1 Hz); 4.70 (d, 1H, J=14.9 Hz); 4.49 (m, 1H); 3.83 (m,1H); 3.05 (m, 1H); 2.86-2.94 (m, 2H); 2.89-2.73 (m, 1H); 2.67-2.57 (m,1H); 2.32-2.19 (brd m, 2H); 2.14-2.06 (brd m, 1H); 1.98-1.90 (m, 2H);1.83-1.68 (brd m, 2H). MS (+FAB) 493.2 ([M+H]⁺); 482.0; 460.1; 307.1;220.2; 176.0; 154.1. Anal. Calc'd for C₂₇H₃₂N₄O₅.HBr.3.3 H₂O: C, 51.23;H, 6.30; N, 8.85. Found: C, 51.19; H, 5.79; N, 8.80.

Example 50 Synthesis ofN-(Benzyl)-L-pyroglutamyl-L-4-(1′-methylpiperidin-4′-yloxy)phenylalanineEthyl Ester

To a solution of N-(benzyl)-pyroglutamic acid (0.29 g, 1.32 mmol),L-4-(1′-methylpiperidin-4′-yloxy)phenylalanine ethyl esterdihydrochloride salt (0.50 g, 1.32 mmol) and BOP (0.64 g, 1.45 mmol) inDMF (15 mL) under nitrogen was added triethylamine (0.65 mL, 4.62 mmol)and the mixture stirred at room temperature for 7 days. The reaction wasquenched by addition of excess saturated sodium bicarbonate solution andEtOAc. The organic phase was separated and concentrated to an oil thatwas flash chromatographed using CH₂Cl₂/MeOH (95:5) as eluent to affordthe product as a solid (0.15 g, 22% yield).

Physical data was as follows:

¹H NMR (DMSO-d₆, 400 MHz) δ 8.57 (d, 1H, J=7.9 Hz); 7.26 (m, 3H); 7.11(d, 2H, J=8.5 Hz); 7.01 (m, 2H); 6.86 (d, 2H, J=8.5 Hz); 4.72 (d, 1H,J=15.1 Hz); 4.52 (m, 1H); 4.33 (brd s, 1H); 4.0-4.1 (brd m, 3H); 3.85(m, 1H); 3.02 (m, 1H); 2.70-2.83 (brd m, 3H); 2.40-2.20 (brd m, 7H);2.12 (m, 1H); 1.93-1.85 (brd s, 2H); 1.75-1.50 (brd m, 4H); 1.21-1.12(m, 3H). MS (EI) 507 ([M+H]⁺); 421; 174; 133; 107; 98; 70. Anal. Calc'dfor C₂₉H₃₇N₃O₅: C, 68.62; H, 7.35; N, 8.28. Found: C, 60.53; H, 6.91; N,8.20.

Example 51 Synthesis ofN-(Benzyl)-L-pyroglutamyl-L-4-(1′-methylpiperidin-4′-yloxy)phenylalanineLithium Salt

To a solution ofN-(benzyl)-L-pyroglutamyl-L-4-(1′-methylpiperidin-4′-yloxy)phenylalanineethyl ester (0.10 g, 0.197 mmol) in MeOH (3 mL) under nitrogen was added1N LiOH solution (0.187 mL, 0.187 mmol). After stirring overnight, thesolvent was evaporated and 10% citric acid solution was added. Aprecipitate was filtered off, washed with water and dried in vacuo toproduce the product as a solid (0.08 g, m p 232-235° C., 83% yield).

Physical data was as follows:

¹H NMR (DMSO-d₆, 400 MHz) δ 7.60 (d, 1H, J=7.2 Hz); 7.25 (m, 3H); 7.01(m, 4H); 6.70 (d, 2H, J=11.4 Hz); 4.71 (d, 1H, J=15.1 Hz); 4.18 (m, 1H);4.02 (m, 1H); 3.87 (m, 1H); 3.05 (m, 1H); 2.85 (m, 1H); 2.57-2.54 (brdm, 2H); 2.28-2.18 (m, 2H); 2.13 (s, 3H); 2.11-2.05 (brd m, 3H);1.87-1.72 (brd m, 3H); 1.58-1.49 (m, 2H). MS (+ESI) 480.1 ([M+H]⁺);352.0; 274.0; 240.9; 179.9.

Example 52 Synthesis ofN-(Benzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalanineEthyl Ester

To a solution of N-(benzyl)-L-pyroglutamyl-L-tyrosine ethyl ester (0.50g, 1.22 mmol), dimethylaminopyridine (0.146 g, 1.20 mmol), triethylamine(0.25 mL, 1.83 mmol) and pyridine (1.5 mL) in CH₂Cl₂ (10 mL) was addeddimethylcarbamyl chloride (0.15 mL, 1.70 mmol) dropwise. After stirringfor 60 h, the reaction was quenched by addition of 10% citric acidsolution (40 mL) followed by extraction using ethyl acetate/hexane(65:35) (100 mL). The organic phase was separated and washedsequentially with water, saturated sodium bicarbonate solution, water,saturated brine, dried with MgSO₄ and evaporated in vacuo to afford theproduct as a solid (0.57 g, mp 150-152° C., 99% yield).

Physical data was as follows:

¹H NMR (DMSO-d₆, 400 MHz) δ 8.59 (d, 1H, J=8.1 Hz); 7.25 (m, 3H); 7.18(d, 2H, J=8.5 Hz); 7.02 (m, 4H); 4.75 (d, 1H, J=15.3 Hz); 4.53 (m, 1H);4.10 (m, 2H); 3.85 (m, 1H); 3.40 (d, 1H, J=15.1 Hz); 3.09 (m, 1H); 3.01(s, 3H); 2.88 (m, 4H); 2.33-2.24 (m, 2H); 2.18-2.08 (m, 1H); 1.76-1.67(m, 1H); 1.14 (t, 3H, J=7.0 Hz). IR (KBr, cm⁻¹) 3425; 2900; 1725; 1690;1660; 1525; 1425; 1380; 1210; 1175; 1010; 845; 800; 750; 650; 520. MS(EI) 481 ([M+H]⁺); 436; 308; 263; 174; 91; 72. Anal. Calc'd forC₂₆H₃₁N₃O₆: C, 64.85; H, 6.49; N, 8.73. Found: C, 65.00; H, 6.55; N,8.70.

Example 53 Synthesis ofN-(Benzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalanineLithium Salt

To a stirred mixture ofN-(benzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalanineethyl ester (0.3 g, 0.62 mmol) in THF (4 mL) was added 1N LiOH solution(0.59 mL, 0.59 mmol) and the mixture was stirred for 72 h. The reactionwas quenched by dilution with water (15-20 mL) and the aqueous phase wasextracted with CH₂Cl₂ three times. Lyophilization of the aqueous layerproduced the product as a solid (0.27 g, 94% yield).

Physical data was as follows:

¹H NMR (DMSO-d₆, 400 MHz) δ 7.54 (d, 1H, J=6.8 Hz); 7.30-7.20 (brd m,3H); 7.10 (d, 2H, J=8.5 Hz); 7.04 (m, 2H); 6.88 (m, 2H); 4.75 (d, 1H,J=15.1 Hz); 3.99 (q, 1H, J=6.3 Hz); 3.86 (m, 1H); 3.41 (d, 1H, J=15.3Hz); 3.11 (m, 1H); 3.00 (s, 3H); 2.88 (m, 4H); 2.30-2.19 (brd m, 2H);2.12-2.05 (m, 1H); 1.79-1.72 (m, 1H). IR (KBr, cm⁻¹) 3400; 2950; 1660;1600; 1400; 1220; 1175; 700; 510. MS (+FAB) 454.0 ([M+H]⁺); 460.0([M+Li]⁺); 410.0; 326.9; 279.0; 220.9; 173.9; 130.6; 80.3. Anal. Calc'dfor C₂₄H₂₇N₃O₆Li.3 H₂O: C, 56.14; H, 6.28; N, 8.18. Found: C, 56.07; H,5.88; N, 7.95.

Example 54 Synthesis ofN-(Benzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalaninetert-Butyl Ester

BOP coupling of N-(benzyl)-L-pyroglutamic acid (1.96 g, 8.9 mmol) andL-tyrosine tert-butyl ester (2.32 g, 9.78 mmol) with triethylamine inDMF according to the method of Example 46 followed by a saturated sodiumbicarbonate quench, addition of EtOAc and extraction with 10% citricacid solution, water, brine, drying (MgSO₄), filtration andconcentration produced the precursorN-(benzyl)-L-pyroglutamyl-L-tyrosine acid tert-butyl ester (3.59 g, mp167-169° C., 92% yield) as a crystalline solid.

Physical data was as follows: Anal. Calc'd for C₂₅H₃₀N₂O₅: C, 68.48; H,6.90; N, 6.39. Found: C, 68.20; H, 6.78; N, 6.75.

To a combined mixture of N-(benzyl)-L-pyroglutamyl-L-tyrosine acidtert-butyl ester (0.5 g, 1.14 mmol), N,N-dimethylaminopyridine (0.14 g,1.14 mmol) and triethylamine (0.24 mL, 1.71 mmol) in CH₂Cl₂ (8 mL) wasadded dimethylcarbamyl chloride (0.15 mL, 1.59 mmol) dropwise. Afterstirring for 66 h, the reaction was quenched by addition of 10% citricacid solution (30 mL) followed by extraction using ethyl acetate/hexane(65:35) mixture (100 mL). The organic phase was separated, washedsequentially with water, saturated sodium bicarbonate solution, water,saturated brine, dried with MgSO₄ and evaporated in vacuo to afford theproduct as a solid (0.52 g, mp 184-185° C., 90% yield).

Physical data was as follows:

¹H NMR (DMSO-d₆, 400 MHz) δ 8.52 (d, 1H, J=8.1 Hz); 7.32-7.20 (m, 5H);7.05-7.01 (m, 4H); 4.76 (d, 1H, J=15.1 Hz); 4.46 (m, 1H); 3.88 (m, 1H);3.40 (d, 1H, J=15.1 Hz); 3.05-3.0 (m, 4H); 2.90 (s, 3H); 2.85 (m, 1H);2.34-2.26 (m, 2H); 2.18-2.11 (m, 1H); 1.78-1.71 (m, 1H); 1.37 (s, 9H).IR (KBr, cm⁻¹) 3410; 3275; 2950; 1725; 1660; 1550; 1430; 1375; 1210;1150; 750; 690; 520. MS (EI) 509 ([M+H]⁺); 453; 408; 233; 174; 91; 72.Anal. Calc'd for C₂₈H₃₅N₃O₆: C, 66.00; H, 6.92; N, 8.25. Found: C,65.88; H, 6.91; N, 8.24.

Example 55 Synthesis ofN-(Benzyl)-L-pyroglutamyl-L-4-[(4′-methylpiperazin-1′-yl)carbonyloxy]phenylalaninetert-Butyl Ester

N-(benzyl)-L-pyroglutamyl-L-tyrosine acid tert-butyl ester (0.50 g, 1.14mmol) was combined with p-nitrophenyl chloroformate (0.218 g, 1.08 mmol)in CH₂Cl₂ (10 mL) and the reaction mixture was cooled to 0° C. under N₂.Triethylamine (0.4 mL, 2.85 mmol), previously dissolved in 2 mL CH₂Cl₂,was added dropwise to the mixture and stirred 30 min at 0° C. Themixture is then brought to ambient temperature and stirred 30 minfollowed by a recooling to 0° C. and addition of 1-methyl-piperazine(0.12 mL, 1.08 mmol). The reaction mixture was then allowed to warm toroom temparature and stired 66 h. The reaction was quenched by dilutionwith Et₂O and washed sequentially with 10% K₂CO₃ solution (5×) and 1NHCl. The acid layer was removed and the pH adjusted to 8 using saturatedsodium bicarbonate solution. Extraction of the aqueous phase with EtOAcand followed by brine wash, drying over MgSO₄, evaporation andrecrystallization (CH₂Cl₂/hexane) produced the product as a solid (0.372g, mp 113-116° C., 58% yield).

Physical data was as follows:

¹H NMR (DMSO-d₆, 400 MHz) δ 8.52 (d, 1H, J=8.1 Hz); 7.30-7.20 (m, 5H);7.03 (m, 4H); 4.76 (d, 1H, J=15.1 Hz); 4.46 (m, 1H); 3.88 (m, 1H); 3.58(brd s, 2H); 3.41 (m, 3H); 2.38-2.32 (brd s, 4H); 2.22 (s, 3H);1.78-1.70 (m, 1H); 1.37 (s, 9H). IR (KBr, cm⁻¹) 3410; 3275; 2925; 1725;1690; 1660; 1550; 1475; 1350; 1290; 1220; 1150; 1050; 1000; 850; 700;510. MS (+ESI) 565.5 ([M+H]⁺); 509.2; 475.5; 344.1; 279.1; 221.0. Anal.Calc'd for C₃₁H₄₀N₄O₆.0.1 CH₂Cl₂: C, 64.96; H, 7.06; N, 9.77. Found: C,64.93; H, 7.10; N, 9.62.

Other compounds prepared by the methods described herein include thoseset forth in Table I above which are not specifically exemplifiedherein.

Example A In vitro Assay For Determining Binding of Candidate Compoundsto VLA-4

An in vitro assay was used to assess binding of candidate compounds toα₄β₁ integrin. Compounds which bind in this assay can be used to assessVCAM-1 levels in biological samples by conventional assays (e.g.,competitive assays). This assay is sensitive to IC₅₀ values as low asabout 1 nM.

The activity of α₄β₁ integrin was measured by the interaction of solubleVCAM-1 with Jurkat cells (e.g., American Type Culture Collection Nos.TIB 152, TIB 153, and CRL 8163), a human T-cell line which expresseshigh levels of α₄β₁ integrin. VCAM-1 interacts with the cell surface inan α₄β₁ integrin-dependent fashion (Yednock, et al. J. Biol. Chem.,1995, 270:28740).

Recombinant soluble VCAM-1 was expressed as a chimeric fusion proteincontaining the seven extracellular domains of VCAM-1 on the N-terminusand the human IgG₁ heavy chain constant region on the C-terminus. TheVCAM-1 fusion protein was made and purified by the manner described byYednock, supra.

Jurkat cells were grown in RPMI 1640 supplemented with 10% fetal bovineserum, penicillin, streptomycin and glutamine as described by Yednock,supra.

Jurkat cells were incubated with 1.5 mM MnCl₂ and 5 μg/mL 15/7 antibodyfor 30 minutes on ice. Mn⁺² activates the receptor to enhance ligandbinding, and 15/7 is a monoclonal antibody that recognizes anactivated/ligand occupied conformation of α₄β₁ integrin and locks themolecule into this conformation thereby stabilizing the VCAM-1/α₄β₁integrin interaction. Yednock, et al., supra. Antibodies similar to the15/7 antibody have been prepared by other investigators (Luque, et al,1996, J. Biol. Chem. 271:11067) and may be used in this assay.

Cells were then incubated for 30 minutes at room temperature withcandidate compounds, in various concentrations ranging from 66 μM to0.01 μM using a standard 5-point serial dilution. 15 μL solublerecombinant VCAM-1 fusion protein was then added to Jurkat cells andincubated for 30 minutes on ice. (Yednock et al., supra.).

Cells were then washed two times and resuspended in PE-conjugated goatF(ab′)₂ anti-mouse IgG Fc (Immunotech, Westbrook, Me.) at 1:200 andincubated on ice, in the dark, for 30 minutes. Cells were washed twiceand analyzed with a standard fluorescence activated cell sorter (“FACS”)analysis as described in Yednock, et al., supra.

Compounds having an IC₅₀ of less than about 15 μM possess bindingaffinity to α₄β₁.

When tested in this assay, each of the compounds in Examples 1-36 had anIC₅₀ of 15 μM or less.

Example B In vitro Saturation Assay For Determining Binding of CandidateCompounds to α₄β₁

The following describes an in vitro assay to determine the plasma levelsneeded for a compound to be active in the Experimental AutoimmuneEncephalomyelitis (“EAE”) model, described in the next example, or inother in vivo models.

Log-growth Jurkat cells are washed and resuspended in normal animalplasma containing 20 μg/ml of the 15/7 antibody (described in the aboveexample).

The Jurkat cells are diluted two-fold into either normal plasma samplescontaining known candidate compound amounts in various concentrationsranging from 66 μM to 0.01 μM, using a standard 12 point serial dilutionfor a standard curve, or into plasma samples obtained from theperipheral blood of candidate compound-treated animals.

Cells are then incubated for 30 minutes at room temperature, washedtwice with phosphate-buffered saline (“PBS”) containing 2% fetal bovineserum and 1 mM each of calcium chloride and magnesium chloride (assaymedium) to remove unbound 15/7 antibody.

The cells are then exposed to phycoerythrin-conjugated goat F(ab′)₂anti-mouse IgG Fc (Immunotech, Westbrook, Me.), which has been adsorbedfor any non-specific cross-reactivity by co-incubation with 5% serumfrom the animal species being studied, at 1:200 and incubated in thedark at 4° C. for 30 minutes.

Cells are washed twice with assay medium and resuspended in the same.They are then analyzed with a standard fluorescence activated cellsorter (“FACS”) analysis as described in Yednock et al. J. Biol. Chem.,1995, 270:28740.

The data is then graphed as fluorescence versus dose, e.g., in a normaldose-response fashion. The dose levels that result in the upper plateauof the curve represent the levels needed to obtain efficacy in an invivo model.

This assay may also be used to determine the plasma levels needed tosaturate the binding sites of other integrins, such as the α₉β₁integrin, which is the integrin most closely related α₄β₁ (Palmer et al,1993, J. Cell Bio., 123:1289). Such binding is predictive of in vivoutility for inflammatory conditions mediated by α₉β₁ integrin, includingby way of example, airway hyper-responsiveness and occlusion that occurswith chronic asthma, smooth muscle cell proliferation inatherosclerosis, vascular occlusion following angioplasty, fibrosis andglomerular scarring as a result of renal disease, aortic stenosis,hypertrophy of synovial membranes in rheumatoid arthritis, andinflammation and scarring that occur with the progression of ulcerativecolitis and Crohn's disease.

Accordingly, the above-described assay may be performed with a humancolon carcinoma cell line, SW 480 (ATTC #CCL228) transfected with cDNAencoding α₉ integrin (Yokosaki et al., 1994, J. Biol. Chem., 269:26691),in place of the Jurkat cells, to measure the binding of the α₉β₁integrin. As a control, SW 480 cells which express other α and β₁subunits may be used.

Accordingly, another aspect of this invention is directed to a methodfor treating a disease in a mammalian patient, which disease is mediatedby α₉β₁, and which method comprises administering to said patient atherapeutically effective amount of a compound of this invention. Suchcompounds are preferably administered in a pharmaceutical compositiondescribed herein above. Effective daily dosing will depend upon the age,weight, condition of the patient which factors can be readilyascertained by the attending clinician. However, in a preferredembodiment, the compounds are administered from about 20 to 500 μg/kgper day.

Example C In vivo Evaluation

The standard multiple sclerosis model, Experimental Autoimmune (orAllergic) Encephalomyelitis (“EAE”), was used to determine the effect ofcandidate compounds to reduce motor impairment in rats or guinea pigs.Reduction in motor impairment is based on blocking adhesion betweenleukocytes and the endothelium and correlates with anti-inflammatoryactivity in the candidate compound. This model has been previouslydescribed by Keszthelyi et al., Neurology, 1996, 47:1053-1059, andmeasures the delay of onset of disease.

Brains and spinal cords of adult Hartley guinea pigs were homogenized inan equal volume of phosphate-buffered saline. An equal volume ofFreund's complete adjuvant (100 mg mycobacterium tuberculosis plus 10 mlFreund's incomplete adjuvant) was added to the homogenate. The mixturewas emulsified by circulating it repeatedly through a 20 ml syringe witha peristaltic pump for about 20 minutes.

Female Lewis rats (2-3 months old, 170-220 g) or Hartley guinea pigs (20day old, 180-200 g) were anesthetized with isoflurane and threeinjections of the emulsion, 0.1 ml each, were made in each flank. Motorimpairment onset is seen in approximately 9 days.

Candidate compound treatment began on Day 8, just before onset ofsymptoms. Compounds were administered subcutaneously (“SC”), orally(“PO”) or intraperitoneally (“IP”). Doses were given in a range of 10mg/kg to 200 mg/kg, bid, for five days, with typical dosing of 10 to 100mg/kg SC, 10 to 50 mg/kg PO, and 10 to 100 mg/kg IP.

Antibody GG5/3 against α₄β₁ integrin (Keszthelyi et al., Neurology,1996, 47:1053-1059), which delays the onset of symptoms, was used as apositive control and was injected subcutaneously at 3 mg/kg on Day 8 and11.

Body weight and motor impairment were measured daily. Motor impairmentwas rated with the following clinical score:

0 no change 1 tail weakness or paralysis 2 hindlimb weakness 3 hindlimbparalysis 4 moribund or dead

A candidate compound was considered active if it delayed the onset ofsymptoms, e.g., produced clinical scores no greater than 2 or slowedbody weight loss as compared to the control.

Example D Asthma Model

Inflammatory conditions mediated by α₄β₁ integrin include, for example,airway hyper-responsiveness and occlusion that occurs with chronicasthma. The following describes an asthma model which can be used tostudy the in vivo effects of the compounds of this invention for use intreating asthma.

Following the procedures described by Abraham et al, J. Clin. Invest,93:776-787 (1994) and Abraham et al, Am J. Respir Crit Care Med,156:696-703 (1997), both of which are incorporated by reference in theirentirety, compounds of this invention are formulated into an aerosol andadministered to sheep which are hypersensitive to Ascaris suum antigen.Compounds which decrease the early antigen-induced bronchial responseand/or block the late-phase airway response, e.g., have a protectiveeffect against antigen-induced late responses and airwayhyper-responsiveness (“AHR”), are considered to be active in this model.

Allergic sheep which are shown to develop both early and late bronchialresponses to inhaled Ascaris suum antigen are used to study the airwayeffects of the candidate compounds. Following topical anesthesia of thenasal passages with 2% lidocaine, a balloon catheter is advanced throughone nostril into the lower esophagus. The animals are then intubatedwith a cuffed endotracheal tube through the other nostril with aflexible fiberoptic bronchoscope as a guide.

Pleural pressure is estimated according to Abraham (1994). Aerosols (seeformulation below) are generated using a disposable medical nebulizerthat provides an aerosol with a mass median aerodynamic diameter of 3.2μm as determined with an Andersen cascade impactor. The nebulizer isconnected to a dosimeter system consisting of a solenoid valve and asource of compressed air (20 psi). The output of the nebulizer isdirected into a plastic T-piece, one end of which is connected to theinspiratory port of a piston respirator. The solenoid valve is activatedfor 1 second at the beginning of the inspiratory cycle of therespirator. Aerosols are delivered at V_(T) of 500 ml and a rate of 20breaths/minute. A 0.5% sodium bicarbonate solution only is used as acontrol.

To assess bronchial responsiveness, cumulative concentration-responsecurves to carbachol can be generated according to Abraham (1994).Bronchial biopsies can be taken prior to and following the initiation oftreatment and 24 hours after antigen challenge. Bronchial biopsies canbe preformed according to Abraham (1994).

An in vitro adhesion study of alveolar macrophages can also be performedaccording to Abraham (1994), and a percentage of adherent cells iscalculated.

Aerosol Formulation

A solution of the candidate compound in 0.5% sodium bicarbonate/saline(w/v) at a concentration of 30.0-100.0 mg/mL is prepared using thefollowing procedure:

A. Preparation of 0.5% Sodium Bicarbonate/Saline Stock Solution: 100.0mL

Ingredient Gram/100.0 mL Final Concentration Sodium Bicarbonate 0.5 g0.5% Saline q.s. ad 100.0 mL q.s. ad 100%

Procedure:

1. Add 0.5 g sodium bicarbonate into a 100 mL volumetric flask.

2. Add approximately 90.0 mL saline and sonicate until dissolved.

3. Q.S. to 100.0 mL with saline and mix thoroughly.

B. Preparation of 30.0 mg/mL Candidate Compound: 10.0 mL

Ingredient Gram/10.0 mL Final Concentration Candidate Compound 0.300 g30.0-100.0 mg/ml 0.5% Sodium q.s. ad 10.0 mL q.s ad 100%Bicarbonate/Saline Stock Solution

Procedure:

1. Add 0.300 g of the candidate compound into a 10.0 mL volumetricflask.

2. Add approximately 9.7 mL of 0.5% sodium bicarbonate/saline stocksolution.

3. Sonicate until the candidate compound is completely dissolved.

4. Q.S. to 10.0 mL with 0.5% sodium bicarbonate/saline stock solutionand mix thoroughly.

Using a conventional oral formulation, compounds of this invention wereactive or are expected to be active in this model when employed at theconcentrations indicated.

What is claimed is:
 1. A compound of formula I or II:

wherein R¹ has the formula:

 wherein R⁶ and R⁷ are independently selected from the group consistingof hydrogen, alkyl, alkoxy, amino, cyano, halo and nitro; and Z is CH orN; R² is selected from the group consisting of alkylene having from 2 to4 carbon atoms in the alkylene chain, substituted alkylene having from 2to 4 carbon atoms in the alkylene chain, heteroalkylene containing from1 to 3 carbon atoms and from 1 to 2 heteroatoms selected from nitrogen,oxygen and sulfur and having from 2 to 4 atoms in the heteroalkylenechain, and substituted heteroalkylene containing, in the heteroalkylenechain, from 1 to 3 carbon atoms and from 1 to 2 heteroatoms selectedfrom nitrogen, oxygen and sulfur and having from 2 to 4 atoms in theheteroalkylene chain; R³ is selected from the group consisting ofhydrogen, alkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl,cycloalkenyl, substituted cycloalkenyl, aryl, substituted aryl,heteroaryl, substituted heteroaryl, heterocyclic, substitutedheterocyclic; or R³ can be joined to R² to form a fused cycloalkyl,substititued cycloalkyl, cycloalkenyl, substituted cycloalkenyl,heterocyclic or substituted heterocyclic ring; X is selected from thegroup consisting of hydrogen, alkyl, substituted alkyl, cycloalkyl,substituted cycloalkyl, alkoxy, substituted alkoxy, aryl, substitutedaryl, aryloxy, substituted aryloxy, aryloxyaryl, substitutedaryloxyaryl, heteroaryl, substituted heteroaryl, heterocyclic,substituted heterocyclic, acylamino, carboxyl, carboxylalkyl,carboxyl-substituted alkyl, carboxyl-cycloalkyl, carboxyl-substitutedcycloalkyl, carboxylaryl, carboxyl-substituted aryl, carboxylheteroaryl,carboxyl-substituted heteroaryl, carboxyheterocyclic,carboxy-substituted heterocyclic, and hydroxyl with the proviso that informula II, X is not hydroxyl; W is oxygen or sulfur; andpharmaceutically acceptable salts thereof.
 2. A compound of formula IAor IIA:

wherein R¹ has the formula:

 wherein R⁶ and R⁷ are independently selected from the group consistingof hydrogen, alkyl, alkoxy, amino, cyano, halo and nitro; and Z is CH orN; R² is selected from the group consisting of alkylene having from 2 to4 carbon atoms in the alkylene chain, substituted alkylene having from 2to 4 carbon atoms in the alkylene chain, heteroalkylene containing from1 to 3 carbon atoms and from 1 to 2 heteroatoms selected from nitrogen,oxygen and sulfur and having from 2 to 4 atoms in the heteroalkylenechain, and substituted heteroalkylene containing, in the heteroalkylenechain, from 1 to 3 carbon atoms and from 1 to 2 heteroatoms selectedfrom nitrogen, oxygen and sulfur and having from 2 to 4 atoms in theheteroalkylene chain; R³ is selected from the group consisting ofhydrogen, alkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl,cycloalkenyl, substituted cycloalkenyl, aryl, substituted aryl,heteroaryl, substituted heteroaryl, heterocyclic, substitutedheterocyclic; or R³ can be joined to R² to form a fused cycloalkyl,substititued cycloalkyl, cycloalkenyl, substituted cycloalkenyl,heterocyclic or substituted heterocyclic ring; X is selected from thegroup consisting of hydrogen, alkyl, substituted alkyl, cycloalkyl,substituted cycloalkyl, alkoxy, substituted alkoxy, aryl, substitutedaryl, aryloxy, substituted aryloxy, aryloxyaryl, substitutedaryloxyaryl, heteroaryl, substituted heteroaryl, heterocyclic,substituted heterocyclic, acylamino, carboxyl, carboxylalkyl,carboxyl-substituted alkyl, carboxyl-cycloalkyl, carboxyl-substitutedcycloalkyl, carboxylaryl, carboxyl-substituted aryl, carboxylheteroaryl,carboxyl-substituted heteroaryl, carboxyheterocyclic,carboxy-substituted heterocyclic, and hydroxyl with the proviso that, informula IIA, X is not hydroxyl; R⁵ is selected from the group consistingof amino, alkoxy, substituted alkoxy, cycloalkoxy, substitutedcycloalkoxy, aryloxy, substituted aryloxy, heteroaryloxy, substitutedheteroaryloxy, heterocyclyloxy, substituted heterocyclyloxy,—NH-adamantyl, —NHSO₂-p-CH₃—φ, —NHOY where Y is hydrogen, alkyl,substituted alkyl, aryl, or substituted aryl, and —NH(CH₂)_(p)COOY′where Y′ is hydrogen, alkyl, substituted alkyl, aryl, or substitutedaryl, and p is an integer of from 1 to 8, —O-cholest-5-en-3-β-yl,—OCH₂—OC(O)C(CH₃)₃, —O(CH₂)_(z)NHC(O)R⁹ where z is 1 or 2 and R⁹ isselected from the group consisting of pyrid-3-yl, N-methylpyridyl, andN-methyl-1,4-dihydro-pyrid-3-yl, —NR″C(O)—R′ where R′ is aryl,heteroaryl or heterocyclic and R″ is hydrogen or —CH₂C(O)OCH₂CH₃; W isoxygen or sulfur; and pharmaceutically acceptable salts thereof; withthe provisos that: (a) when R¹ is benzyl, R² is —CH₂CH₂—, R³ ishydrogen, —CH₂X is benzyl, then R⁵ is not ethyl; (b) when R¹ is3,4-dichlorobenzyl, R² is —CH₂CH₂—, R³ is hydrogen, —CH₂X is4-(phenylcarbonylamino)benzyl, then R⁵ is not methyl; (c) when R¹ isbenzyl, R² is —CH₂CH₂—, R³ is hydrogen, —CH₂X is 4-hydroxybenzyl, thenR⁵ is not isopropyl or tert-butyl; (d) when R¹ is 4-fluorobenzyl, R² is—CH₂CH₂—, R³ is hydrogen, R⁵ is tert-butyl, then —CH₂X is not4-hydroxybenzyl or 4-(4-nitrophenoxy-carbonyloxy)benzyl; and (e) when R¹is 4-cyanobenzyl, R² is —CH₂CH₂—, R³ is hydrogen, —CH₂X is4-hydroxybenzyl, then R⁵ is not tert-butyl.
 3. The compound according toclaim 1 or 2 wherein Z is CH.
 4. The compound according to claim 3wherein one of R⁶ and R⁷ is hydrogen and the other is selected from thegroup consisting of hydrogen, methyl, methoxy, amino, chloro, fluoro,cyano or nitro; or both R⁶ and R⁷ are chloro.
 5. The compound accordingto claim 1 or 2 wherein R¹ is selected from the group consisting ofbenzyl, 4-aminobenzyl, 3-chlorobenzyl, 4-chlorobenzyl,3,4-dichlorobenzyl, 4-cyanobenzyl, 4-fluorobenzyl, 4-methylbenzyl,4-methoxybenzyl, 4-nitrobenzyl, and (pyridin-3-yl)methyl.
 6. Thecompound according to claim 1 or 2 wherein R² is selected from the groupconsisting of alkylene having 2 or 3 carbon atoms in the alkylene chain,substituted alkylene having 2 or 3 carbon atoms in the alkylene chain,heteroalkylene containing 1 or 2 carbon atoms and 1 heteroatom selectedfrom nitrogen, oxygen and sulfur and having 2 or 3 atoms in theheteroalkylene chain, and substituted heteroalkylene containing, in theheteroalkylene chain, 1 or 2 carbon atoms and 1 heteroatom selected fromnitrogen, oxygen and sulfur and having 2 or 3 atoms in theheteroalkylene chain.
 7. The compound according to claim 6 wherein R² isselected from the group consisting of —CH₂CH₂—, —CH₂—S—CH₂—, —CH₂—O—CH₂—and —NHCH₂—.
 8. The compound according to claim 1 or 2 wherein R³ ishydrogen.
 9. The compound according to claim 1 or 2 wherein R³ is joinedto R² to form a fused and/or bridged cycloalkyl, substituted cycloalkyl,cycloalkenyl, substititued cycloalkenyl, heterocyclic or substitutedheterocyclic ring.
 10. The compound according to claim 9 wherein R² andR³, together with the other atoms of the nitrogen-containing ring form a5-oxo-4-azatricyclo[4.2.1.0(3,7)]nonane ring.
 11. The compound accordingto claim 1 or 2 wherein W is oxygen.
 12. The compound according to claim2 wherein R⁵ is selected from the group consisting of2,4-dioxo-tetrahydrofuran-3-yl (3,4-enol), methoxy, ethoxy, iso-propoxy,n-butoxy, t-butoxy, cyclopentoxy, neo-pentoxy,2-α-iso-propyl-4-β-methylcyclohexoxy,2-p-isopropyl4-β-methylcyclohexoxy, —NH₂, benzyloxy, —NHCH₂COOH,—NHCH₂CH₂COOH, —NH-adamantyl, —NHCH₂CH₂COOCH₂CH₃, —NHSO₂-p-CH₃—φ, —NHOR⁸where R⁸ is hydrogen, methyl, iso-propyl or benzyl, O—(N-succinimidyl),—O—cholest-5-en-3-β-yl, —OCH₂—OC(O)C(CH₃)₃, —O(CH₂)_(z)NHC(O)R⁹ where zis 1 or 2 and R⁹ is selected from the group consisting of pyrid-3-yl,N-methylpyridyl, and N-methyl-1,4-dihydro-pyrid-3-yl, —NR″C(O)—R′ whereR′ is aryl, heteroaryl or heterocyclic and R″ is hydrogen or—CH₂C(O)OCH₂CH₃.
 13. The compound according to claim 1 or 2 wherein—CH₂X is selected from the group consisting of: 4-methylbenzyl,4-hydroxybenzyl, 4-methoxybenzyl, 4-t-butoxybenzyl, 4-benzyloxybenzyl,4-[φ—CH(CH₃)O—]benzyl, 4-[φ—CH(COOH)O—]benzyl,4-[BocNHCH₂C(O)NH—]benzyl, 4-chlorobenzyl, 4-[NH₂CH₂C(O)NH—]benzyl,4-carboxybenzyl, 4-[CbzNHCH₂CH₂NH—]benzyl,3-hydroxy-4-(φ—OC(O)NH—)benzyl, 4-[HOOCCH₂CH₂C(O)NH—]benzyl, benzyl,4-[2′-carboxylphenoxy-]benzyl, 4-[φ—C(O)NH—]benzyl, 3-carboxybenzyl,4-iodobenzyl, 4-hydroxy-3,5-diiodobenzyl, 4-hydroxy-3-iodobenzyl,4-[2′-carboxyphenyl-]benzyl, φ—CH₂CH₂—; 4-nitrobenzyl, 2-carboxybenzyl,4-[dibenzylamino]-benzyl,4-[(1′-cyclopropylpiperidin-4′-yl)C(O)NH—]benzyl,4-[—NHC(O)CH₂NHBoc]benzyl, 4-carboxybenzyl, 4-hydroxy-3-nitrobenzyl,4-[—NHC(O)CH(CH₃)NHBoc]benzyl, 4-[—NHC(O)CH(CH₂φ)NHBoc]benzyl, isobutyl,methyl, 4-[CH₃C(O)NH—]benzyl, (3-indolyl)-CH₂—, n-butyl,t-butyl-OC(O)CH₂—, t-butyl-OC(O)CH₂CH₂—, H₂NC(O)CH₂—, H₂NC(O)CH₂CH₂—,BocNH—(CH₂)₄—, t-butyl-OC(O)—(CH₂)₂—, HOOCCH₂—, HOOC(CH₂)₂—, H₂N(CH₂)₄—,isopropyl, (1-naphthyl)-CH₂—, (2-naphthyl)-CH₂—, (2-thiophenyl)-CH₂—,φ—CH₂—OC(O)NH—(CH₂)₄—, cyclohexyl-CH₂—, benzyloxy-CH₂—, HOCH₂—,5-(3-N-benzyl)imidazolyl-CH₂—, 2-pyridyl-CH₂—, 3-pyridyl-CH₂—,4-pyridyl-CH₂—, 5-(3-N-methyl)imidazolyl-CH₂—,N-benzylpiperid-4-yl-CH₂—, N-Boc-piperidin-4-yl-CH₂—,N-(phenyl-carbonyl)piperidin-4-yl-CH₂—, H₃CSCH₂CH₂—,1-N-benzylimidazol-4-yl-CH₂—, iso-propyl-C(O)NH—(CH₂)₄—,iso-butyl-C(O)NH—(CH₂)₄—, phenyl-C(O)NH—(CH₂)₄—, benzyl-C(O)NH—(CH₂)₄—,allyl-C(O)NH—(CH₂)₄—, 4-(3-N-methylimidazolyl)-CH₂—, 4-imidazolyl-CH₂—,4-[(CH₃)₂NCH₂CH₂CH₂—O—]benzyl, 4-[(benzyl)₂N—]-benzyl, 4-aminobenzyl,allyloxy-C(O)NH(CH₂)₄—, allyloxy-C(O)NH(CH₂)₃—, allyloxy-C(O)NH(CH₂)₂—,NH₂C(O)CH₂—, 2-pyridyl-C(O)NH—(CH₂)₄—,4-methylpyrid-3-yl-C(O)NH—(CH₂)₄—, 3-methylene-2-yl-C(O)NH—(CH₂)₄—,2-pyrrolyl-C(O)NH—(CH₂)₄—, 2-furanyl-C(O)NH—(CH₂)₄—,4-methylphenyl-SO₂—N(CH₃)CH₂C(O)NH(CH₂)₄—,4-[cyclopentylacetylenyl]-benzyl,4-[—NHC(O)-(N-Boc)-pyrrolidin-2-yl)]-benzyl,1-N-methylimidazol-4-yl-CH₂—, 1-N-methylimidazol-5-yl-CH₂—,imidazol-5-yl-CH₂—, 6-methylpyrid-3-yl-C(O)NH—(CH₂)₄—,4-[2′-carboxymethylphenyl]-benzyl, 4-[—NHC(O)NHCH₂CH₂CH₂—φ]-benzyl,4-[—NHC(O)NHCH₂CH₂—φ]-benzyl, —CH₂C(O)NH(CH₂)₄φ, 4-[φ(CH₂)₄O—]-benzyl,4-[—C≡C—φ-4′φ]-benzyl, 4-[—C≡C—CH₂—O—S(O)₂-4′-CH₃-φ]-benzyl,4-[—C≡C—CH₂NHC(O)NH₂]-benzyl, 4-[—C≡C—CH₂—O-4′-COOCH₂CH₃—φ]-benzyl,4-[—C≡C—CH(NH₂)-cyclohexyl]-benzyl, —(CH₂)₄NHC(O)CH₂-3-indolyl,—(CH₂)₄NHC(O)CH₂CH₂-3-indolyl, —(CH₂)₄NHC(O)-3-(5-methoxyindolyl),—(CH₂)₄NHC(O)-3-(1-methylindolyl), —(CH₂)₄NHC(O)-4-(—SO₂(CH₃)—φ),—(CH₂)₄NHC(O)-4-(C(O)CH₃)-phenyl, —(CH₂)₄NHC(O)-4-fluorophenyl,—(CH₂)₄NHC(O)CH₂O-4-fluorophenyl, 4-[—C≡C-(2-pyridyl)]benzyl,4-[—C≡C—CH₂—O-phenyl]benzyl, 4-[—C≡C—CH₂OCH₃]benzyl,4-[—C≡C-(3-hydroxyphenyl)]benzyl,4-[—C≡C—CH₂—O-4′-(—C(O)OC₂H₅)phenyl]benzyl,4-[—C≡C—CH₂CH(C(O)OCH₃)₂]benzyl, 3-aminobenzyl,4-[—C≡C—CH₂CH(NHC(O)CH₃)C(O)OH]-benzyl, —CH₂C(O)NHCH(CH₃)φ,—CH₂C(O)NHCH₂-(4-dimethylamino)-φ, —CH₂C(O)NHCH₂-4-nitrophenyl,—CH₂CH₂C(O)N(CH₃)CH₂—φ, —CH₂CH₂C(O)NHCH₂CH₂-(N-methyl)-2-pyrrolyl,—CH₂CH₂C(O)NHCH₂CH₂CH₂CH₃, —CH₂CH₂C(O)NHCH₂CH₂-3-indolyl,—CH₂C(O)N(CH₃)CH₂phenyl, —CH₂C(O)NH(CH₂)₂-(N-methyl)-2-pyrrolyl,—CH₂C(O)NHCH₂CH₂CH₂CH₃, —CH₂C(O)NHCH₂CH₂-3-indolyl,—(CH₂)₂C(O)NHCH(CH₃)φ, —(CH₂)₂C(O)NHCH₂-4-dimethylaminophenyl,—(CH₂)₂C(O)NHCH₂-4-nitrophenyl, —CH₂C(O)NH-4-[—NHC(O)CH₃-phenyl],—CH₂C(O)NH-4-pyridyl, —CH₂C(O)NH-4-[dimethylaminophenyl],—CH₂C(O)NH-3-methoxyphenyl, —CH₂CH₂C(O)NH-4-chlorophenyl,—CH₂CH₂C(O)NH-2-pyridyl, —CH₂CH₂C(O)NH-4-methoxyphenyl,—CH₂CH₂C(O)NH-3-pyridyl, 4-[(CH₃)₂NCH₂CH₂O—]benzyl,—(CH₂)₃NHC(NH)NH—SO₂-4-methylphenyl, 4-[(CH₃)₂NCH₂CH₂O—]benzyl,—(CH₂)₄NHC(O)NHCH₂CH₃, —(CH₂)₄NHC(O)NH-phenyl,—(CH₂)₄NHC(O)NH-4-methoxyphenyl, 4-[4′-pyridyl-C(O)NH—]benzyl,4-[3′-pyridyl-C(O)NH—]benzyl, 4-[—NHC(O)NH-3′-methylphenyl]benzyl,4-[—NHC(O)CH₂NHC(O)NH-3′-methylphenyl]benzyl,4-[—NHC(O)-(2′,3′-dihydroindol-2-yl)]benzyl,4-[—NHC(O)-(2′,3′-dihydro-N-Boc-indol-2-yl)]benzyl,p-[—OCH₂CH₂-1′-(4′-pyrimidinyl)-piperazinyl]benzyl,4-[—OCH₂CH₂-(1′-piperidinyl)]benzyl,4-[—OCH₂CH₂-(1′-pyrrolidinyl)]benzyl,4-[—OCH₂CH₂CH₂-(1′-piperidinyl)]benzyl, —CH₂-3-(1,2,4-triazolyl),4-[—OCH₂CH₂CH₂-4-(3′-chlorophenyl)-piperazin-1-yl]benzyl,4-[—OCH₂CH₂N(φ)CH₂CH₃]benzyl, 4-[—OCH₂-3′-(N-Boc)-piperidinyl]benzyl,4-[di-n-pentylamino]benzyl, 4-[n-pentylamino]benzyl,4-[di-iso-propylamino-CH₂CH₂O—]benzyl,4-[—OCH₂CH₂-(N-morpholinyl)]benzyl,4-[—O-(3′-(N-Boc)-piperidinyl)]benzyl,4-[—OCH₂CH(NHBoc)CH₂cyclohexyl]benzyl, p-[OCH₂CH₂-(N-piperidinyl]benzyl,4-[—OCH₂CH₂CH₂-(4-m-chlorophenyl)-piperazin-1-yl]benzyl,4-[—OCH₂CH₂-(N-homopiperidinyl)]benzyl,4-[—NHC(O)-3′-(N-Boc)-piperidinyl]benzyl, 4-[—OCH₂CH₂N(benzyl)]benzyl,—CH₂-2-thiazolyl, 3-hydroxybenzyl, 4-[—OCH₂CH₂CH₂N(CH₃)₂]benzyl,4-[—NHC(S)NHCH₂CH₂-(N-morpholino)]benzyl, 4-[—OCH₂CH₂N(C₂H₅)₂]benzyl,4-[—OCH₂CH₂CH₂N(C₂H₅)₂]benzyl, 4-[CH₃(CH₂)₄NH—]benzyl, 4-[N-n-butyl,N-n-pentylamino-]benzyl, 4-[—NHC(O)-4′-piperidinyl]benzyl,4-[—NHC(O)CH(NHBoc)(CH₂)₄NHCbz]benzyl,4-[—NHC(O)-(1′,2′,3′,4′-tetrahydro-N-Boc-isoquinolin-1′-yl)]benzyl,p-[—OCH₂CH₂CH₂-1′-(4′-methyl)-piperazinyl]benzyl, —(CH₂)₄NH-Boc,3-[—OCH₂CH₂CH₂N(CH₃)₂]benzyl, 4-[—OCH₂CH₂CH₂N(CH₃)₂]benzyl,3-[—OCH₂CH₂-(1′-pyrrolidinyl)]benzyl, 4-[—OCH₂CH₂CH₂N(CH₃)benzyl]benzyl,4-[—NHC(S)NHCH₂CH₂CH₂-(N-morpholino)]benzyl,4-[—OCH₂CH₂-(N-morpholino)]benzyl, 4-[—NHCH₂-(4′-chlorophenyl)]benzyl,4-[—NHC(O)NH—(4′-cyanophenyl)]benzyl, 4-[—OCH₂COOH]benzyl,4-[—OCH₂COO-t-butyl]benzyl, 4-[—NHC(O)-5′-fluoroindol-2-yl]benzyl,4-[—NHC(S)NH(CH₂)₂-1-piperidinyl]benzyl,4-[—N(SO₂CH₃)(CH₂)₃—N(CH₃)₂]benzyl,4-[—NHC(O)CH₂CH(C(O)OCH₂φ)—NHCbz]benzyl, 4-[—NHS(O)₂CF₃]benzyl,3-[—O-(N-methylpiperidin-4′-yl]benzyl, 4-[—C(═NH)NH₂]benzyl,4-[—NHSO₂—CH₂Cl]benzyl,4-[—NHC(O)-(1′,2′,3′,4′-tetrahydroisoquinolin-2′-yl)]benzyl,4-[—NHC(S)NH(CH₂)₃—N-morpholino]benzyl,4-[—NHC(O)CH(CH₂CH₂CH₂CH₂NH₂)NHBoc]benzyl, 4-[—C(O)NH₂]benzyl,4-[—NHC(O)NH-3′-methoxyphenyl]benzyl, 4-[—OCH₂CH₂-indol-3′-yl]benzyl,4-[—OCH₂C(O)NH-benzyl]benzyl, 4-[—OCH₂C(O)O-benzyl]benzyl,4-[—OCH₂C(O)OH]benzyl, 4-[—OCH₂-2′-(4′,5′-dihydro)imidazolyl]benzyl,—CH₂C(O)NHCH₂-(4-dimethylamino)phenyl,—CH₂C(O)NHCH₂-(4-dimethylamino)phenyl,4-[—NHC(O)-L-2′-pyrrolidinyl-N—SO₂-4′-methylphenyl]benzyl,4-[—NHC(O)NHCH₂CH₂CH₃]benzyl, 4-[aminobenzyl]benzyl,4-[—OCH₂CH₂-1-(4-hydroxy-4-(3-methoxypyrrol-2-yl)piperazinyl)]benzyl,4-[—O-(N-methylpiperidin-4′-yl)]benzyl, 3-methoxybenzyl,4-[—NHC(O)-piperidin-3′-yl]benzyl, 4-[—NHC(O)-pyridin-2′-yl]benzyl,4-[—NHCH₂-(4′-chlorophenyl)]benzyl,4-[—NHC(O)-(N-(4′-CH₃—φ—SO₂)-L-pyrrolidin-2′-yl)]benzyl,4-[—NHC(O)NHCH₂CH₂—φ]benzyl, 4-[—OCH₂C(O)NH₂]benzyl,4-[—OCH₂C(O)NH-t-butyl]benzyl,4-[—OCH₂CH₂-1-(4-hydroxy-4-phenyl)-piperidinyl]benzyl,4-[—NHSO₂—CH═CH₂]benzyl, 4-[—NHSO₂—CH₂CH₂Cl]benzyl,—CH₂C(O)NHCH₂CH₂N(CH₃)₂, 4-[(1′-Cbz-piperidin-4′-yl)C(O)NH—]benzyl,4-[(1′-Boc-piperidin-4′-yl)C(O)NH—]benzyl,4-[(2′-bromophenyl)C(O)NH—]benzyl, 4-[—NHC(O)-pyridin-4′-yl]benzyl,4-[(4′-(CH₃)₂NC(O)O—)phenyl)-C(O)NH—]benzyl,4-[—NHC(O)-1′-methylpiperidin-4′-yl-]benzyl, 4-(dimethylamino)benzyl,4-[—NHC(O)-(1′-N-Boc)-piperidin-2′-yl]benzyl,3-[—NHC(O)-pyridin-4′-yl]benzyl,4-[(tert-butyl-O(O)CCH₂—O-benzyl)-NH—]benzyl, {BocNHCH₂C(O)NH—}butyl,4-benzylbenzyl, 2-hydroxyethyl, 4-[(Et)₂NCH₂CH₂CH₂NHC(S)NH—]benzyl,4-[(1′-Boc-4′-hydroxypyrrolidin-2′-yl)C(O)NH—]benzyl,4-[φCH₂CH₂CH₂NHC(S)NH—]benzyl, 4-[(perhydroindolin-2′-yl)C(O)NH—]benzyl,2-[4-hydroxy-4-(3-methoxythien-2-yl)piperidin-1-yl]ethyl,4-[(1′-Boc-perhydroindolin-2′-yl)-C(O)NH—]benzyl,4-[(N-3-methylbutyl-N-trifluoromethanesulfonyl)amino]benzyl,4-[(N-vinylsulfonyl)amino]benzyl,4-[2-(2-azabicyclo[3.2.2]octan-2-yl)ethyl-O—]benzyl,4-[4′-hydroxypyrrolidin-2′-yl)C(O)NH—]benzyl, 4-(φNHC(S)NH)benzyl,4-(EtNHC(S)NH)benzyl, 4-(φCH₂NHC(S)NH)benzyl,3-[(1′-Boc-piperidin-2′-yl)C(O)NH—]benzyl,3-[piperidin-2′-yl-C(O)NH—]benzyl,4-[(3′-Boc-thiazolidin-4′-yl)C(O)NH—]benzyl,4-(pyridin-3′-yl-NHC(S)NH)benzyl, 4-(CH₃—NHC(S)NH)benzyl,4-(H₂NCH₂CH₂CH₂C(O)NH)benzyl, 4-(BocHNCH₂CH₂CH₂C(O)NH)benzyl,4-(pyridin-4′-yl-CH₂NH)benzyl,4-[(N,N-di(4-N,N-dimethylamino)benzyl)amino]benzyl,4-[(1-Cbz-piperidin-4-yl)C(O)NH—]butyl,4-[φCH₂OCH₂(BocHN)CHC(O)NH]benzyl, 4-[(piperidin-4′-yl)C(O)NH—]benzyl,4-[(pyrrolidin-2′-yl)C(O)NH—]benzyl, 4-(pyridin-3′-yl-C(O)NH)butyl,4-(pyridin-4′-yl-C(O)NH)butyl, 4-(pyridin-3′-yl-C(O)NH)benzyl,4-[CH₃NHCH₂CH₂CH₂C(O)NH—]benzyl, 4-[CH₃N(Boc)CH₂CH₂CH₂C(O)NH—]benzyl,4-(aminomethyl)benzyl, 4-[φCH₂OCH₂(H₂N)CHC(O)NH]benzyl,4-[(1′,4′-di(Boc)piperazin-2′-yl)-C(O)NH—]benzyl,4-[(piperazin-2′-yl)-C(O)NH—]benzyl,4-[(N-toluenesulfonylpyrrolidin-2′-yl)C(O)NH—]butyl,4-[—NHC(O)-4′-piperidinyl]butyl,4-[—NHC(O)-1′-N-Boc-piperidin-2′-yl]benzyl,4-[—NHC(O)-piperidin-2′-yl]benzyl,4-[(1′-N-Boc-2′,3′-dihydroindolin-2′-yl)-C(O)NH]benzyl,4-(pyridin-3′-yl-CH₂NH)benzyl, 4-[(piperidin-1′-yl)C(O)CH₂—O—]benzyl,4-[(CH₃)₂CH₂NC(O)CH₂—O—]benzyl,4-[HO(O)C(Cbz-NH)CHCH₂CH₂—C(O)NH—]benzyl,4-[φCH₂O(O)C(Cbz-NH)CHCH₂CH₂—C(O)NH—]benzyl,4-[—NHC(O)-2′-methoxyphenyl]benzyl, 4-[(pyrazin-2′-yl)C(O)NH—]benzyl,4-[HO(O)C(NH₂)CHCH₂CH₂—C(O)NH—]benzyl,4-(2′-formyl-1′,2′,3′,4′-tetrahydroisoquinolin-3′-yl-CH₂NH—)benzyl,N-Cbz-NHCH₂—, 4-[(4′-methylpiperazin-1′-yl)C(O)O—]benzyl,4-[CH₃(N-Boc)NCH₂C(O)NH—]benzyl,4-[—NHC(O)-(1′,2′,3′,4′-tetrahydro-N-Boc-isoquinolin-3′-yl]-benzyl,4-[CH₃NHCH₂C(O)NH—]benzyl, (CH₃)₂NC(O)CH₂—, 4-(N-methylacetamido)benzyl,4-(1′,2′,3′,4′-tetrahydroisoquinolin-3′-yl-CH₂NH—)benzyl,4-[(CH₃)₂NHCH₂C(O)NH—]benzyl, (1-toluenesulfonylimidizol-4-yl)methyl,4-[(1′-Boc-piperidin-4′-yl)C(O)NH—]benzyl, 4-trifluoromethylbenzyl,4-[(2′-bromophenyl)C(O)NH—]benzyl, 4-[(CH₃)₂NC(O)NH—]benzyl,4-[CH₃OC(O)NH—]benzyl, 4-[(CH₃)₂NC(O)O—]benzyl,4-[(CH₃)₂NC(O)N(CH₃)—]benzyl, 4-[CH₃OC(O)N(CH₃)—]benzyl,4-(N-methyltrifluoroacetamido)benzyl,4-[(1′-methoxycarbonylpiperidin-4′-yl)C(O)NH—]benzyl,4-[(4′-phenylpiperidin-4′-yl)C(O)NH—]benzyl,4-[(4′-phenyl-1′-Boc-piperidin-4′-yl)-C(O)NH—]benzyl,4-[(piperidin-4′-yl)C(O)O—]benzyl,4-[(1′-methylpiperidin-4′-yl)-O—]benzyl,4-[(1′-methylpiperidin-4′-yl)C(O)O—]benzyl,4-[(4′-methylpiperazin-1′-yl)C(O)NH—]benzyl, 3-[(CH₃)₂NC(O)O—]benzyl,4-[(4′-phenyl-1′-Boc-piperidin-4′-yl)-C(O)O—]benzyl,4-(N-toluenesulfonylamino)benzyl, 4-[(CH₃)₃CC(O)NH—]benzyl,4-[(morpholin-4′-yl)C(O)NH—]benzyl, 4-[(CH₃CH₂)₂NC(O)NH—]benzyl,4-[—C(O)NH—(4′-piperidinyl)]benzyl,4-[(2′-trifluoromethylphenyl)C(O)NH—]benzyl,4-[(2′-methylphenyl)C(O)NH—]benzyl, 4-[(CH₃)₂NS(O)₂O—]benzyl,4-[(pyrrolidin-2′-yl)C(O)NH—]benzyl, 4-[—NHC(O)-piperidin-1′-yl]benzyl,4-[(thiomorpholin-4′-yl)C(O)NH—]benzyl, 4-[(thiomorpholin-4′-ylsulfone)-C(O)NH—]benzyl, 4-[(morpholin-4′-yl)C(O)O—]benzyl,3-nitro-4-(CH₃OC(O)CH₂O—)benzyl, (2-benzoxazolinon-6-yl)methyl-,(2H-1,4-benzoxazin-3(4H)-one-7-yl)methyl-, 4-[(CH₃)₂NS(O)₂NH—]benzyl,4-[(CH₃)₂NS(O)₂N(CH₃)—]benzyl, 4-[(thiomorpholin-4′-yl)C(O)O—]benzyl,4-[(thiomorpholin-4′-yl sulfone)-C(O)O—]benzyl,4-[(piperidin-1′-yl)C(O)O—]benzyl, 4-[(pyrrolidin-1′-yl)C(O)O—]benzyl,4-[(4′-methylpiperazin-1′-yl)C(O)O—]benzyl, (pyridin-4-yl)methyl-,4-[(piperazin-4′-yl)-C(O)O—]benzyl,4-[(1′-Boc-piperazin-4′-yl)-C(O)O—]benzyl,4-[(4′-acetylpiperazin-1′-yl)C(O)O—]benzyl,p-[(4′-methanesulfonylpiperazin-1′-yl)-benzyl,3-nitro-4-[(morpholin-4′-yl)-C(O)O—]benzyl, 4-{[(CH₃)₂NC(S)]₂N-}benzyl,N-Boc-2-aminoethyl-, 4-[(1,1-dioxothiomorpholin-4-yl)-C(O)O—]benzyl,4-[(CH₃)₂NS(O)₂—]benzyl, 4-(imidazolid-2′-one-1′-yl)benzyl,4-[(piperidin-1′-yl)C(O)O—]benzyl, 1-N-benzyl-imidazol-4-yl-CH₂—,3,4-dioxyethylenebenzyl, 3,4-dioxymethylenebenzyl,4-[—N(SO₂)(CH₃)CH₂CH₂CH₂N(CH₃)₂]benzyl,4-(3′-formylimidazolid-2′-one-1′-yl)benzyl,4-[NHC(O)CH(CH₂CH₂CH₂CH₂NH₂)NHBoc]benzyl,{2′-[4″-hydroxy-4″-(3′″-methoxythien-2′″-yl)piperidin-2″-yl]ethoxy}benzyl,and p-[(CH₃)₂NCH₂CH₂N(CH₃)C(O)O—]benzyl.
 14. The compound according toclaim 1 or 2 wherein —CH₂X is selected from the group consisting of:benzyl, 4-aminobenzyl, 4-hydroxybenzyl, 4-nitrobenzyl,3-chloro-4-hydroxybenzyl, 4-(phenylC(O)NH—)benzyl,4-(pyridin-4-ylC(O)NH—)benzyl, 4-[(CH₃)₂NC(O)O—]benzyl,4-[(1′-Cbz-piperidin-4′-yl)C(O)NH—]benzyl,4-[(piperidin-4′-yl)C(O)NH—]benzyl,4-[—O-(N-methylpiperidin-4′-yl)]benzyl,4-[(4′-methylpiperazin-1′-yl)C(O)O—]benzyl,4-[(4′-(pyridin-2-yl)piperazin-1′-yl)C(O)O—]benzyl,4-[(thiomorpholin-4′-yl)C(O)O—]benzyl, 3-chloro-4-[(CH₃)₂NC(O)O—]benzyl,and 5-(3-N-benzyl)imidazolyl-CH₂—.
 15. The compound according to claim 1or 2 wherein ═CHX is ═CHφ.
 16. A compound selected from the groupconsisting of: N-(benzyl)-L-pyroglutamyl-L-phenylalanineN-(benzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalanineN-(3,4-dichlorobenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalanineN-(3-chlorobenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalanineN-(3-chlorobenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalaninemethyl esterN-(4-chlorobenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalanineN-(4-chlorobenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalaninemethyl esterN-(4-methylbenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalanineN-(4-methylbenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalaninemethyl esterN-(4-methoxybenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalanineN-(4-methoxybenzyl)-L-pyroglutamyl-L-4-(phenylcarbonylamino)phenylalaninemethyl ester N-(3-chlorobenzyl)-L-pyroglutamyl-L-(N′-benzyl)histidineN-(4-methylbenzyl)-L-pyroglutamyl-L-(N′-benzyl)histidine methyl esterN-(4-methylbenzyl)-L-pyroglutamyl-L-(N′-benzyl)histidineN-(benzyl)-D-pyroglutamyl-L-phenylalanineN-(4-benzyl-3-oxothiomorpholin-5-carbonyl)-L-phenylalanineN-(4-benzyl-3-oxothiomorpholin-5-carbonyl)-L-phenylalanine ethyl esterN-(4-benzyl-3-oxomorpholin-5-carbonyl)-L-phenylalanineN-(4-benzyl-3-oxothiomorpholin-5-carbonyl)-L-4-nitrophenylalanine methylesterN-(benzyl)-L-pyroglutamyl-L-4-(pyridin-4-ylcarbonylamino)phenylalaninemethyl esterN-(benzyl)-L-pyroglutamyl-L-4-(1′-benzyloxycarbonylpiperidin-4′-ylcarbonylamino)phenylalaninemethyl esterN-(benzyl)-L-pyroglutamyl-L-4-(pyridin-4-ylcarbonylamino)phenylalanineN-(benzyl)-L-pyroglutamyl-L-4-(1′-benzyloxycarbonylpiperidin-4′-ylcarbonylamino)phenylalanineN-(benzyl)-L-pyroglutamyl-L-tyrosine ethyl esterN-(benzyl)-L-pyroglutamyl-L-4-(piperidin-4′-ylcarbonylamino)phenylalanineN-(benzyl)-L-pyroglutamyl-L-4-nitrophenylalanine ethyl esterN-(benzyl)-L-pyroglutamyl-L-tyrosineN-(benzyl)-L-pyroglutamyl-L-4-(1′-methylpiperidin-4′-yloxy)phenylalanineethyl ester N-(benzyl)-L-pyroglutamyl-L-4-nitrophenylalanineN-(benzyl)-L-pyroglutamyl-L-4-[(4′-methylpiperazin-1′-yl)carbonyloxy]phenylalanineethyl esterN-(benzyl)-L-pyroglutamyl-L-4-(1′-methylpiperidin-4′-yloxy)phenylalanine-(benzyl)-L-pyroglutamyl-L-4-[(4′-methylpiperazin-1′-yl)carbonyloxy]phenylalanineN-(benzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalanineethyl ester N-(benzyl)-L-pyroglutamyl-L-4-aminophenylalanine ethyl esterN-(benzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalanineN-(benzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalaninetert-butyl esterN-(benzyl)-L-pyroglutamyl-L-4-[(4′-methylpiperazin-1′-yl)carbonyloxy]phenylalaninetert-butyl esterN-(benzyl)-L-pyroglutamyl-L-4-[(thiomorpholin-4′-yl)carbonyloxy]phenylalaninetert-butyl esterN-(4-fluorobenzyl)-L-pyroglutamyl-L-4-[(thiomorpholin-4′-yl)carbonyloxy]phenylalaninetert-butyl esterN-(benzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalanineisopropyl esterN-(4-fluorobenzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalaninetert-butyl esterN-(benzyl)-L-pyroglutamyl-L-3-chloro-4-hydroxyphenylalanineN-(4-cyanobenzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalaninetert-butyl esterN-(benzyl)-L-pyroglutamyl-L-3-chloro-4-(N,N-dimethylcarbamyloxy)phenylalaninemethyl esterN-(4-fluorobenzyl)-L-pyroglutamyl-L-4-[(thiomorpholin-4′-yl)carbonyloxy]phenylalanineN-(4-cyanobenzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalanineN-(4-nitrobenzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalaninetert-butyl esterN-(benzyl)-L-pyroglutamyl-L-3-chloro-4-(N,N-dimethylcarbamyloxy)phenylalanineN-(4-fluorobenzyl)-L-pyroglutamyl-L-4-[(4′-(pyridin-2-yl)piperazin-1′-yl)carbonyloxy]phenylalanineN-(4-fluorobenzyl)-L-pyroglutamyl-L-4-[(4′-(pyridin-2-yl)piperazin-1′-yl)carbonyloxy]phenylalaninetert-butyl esterN-(4-aminobenzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalaninetert-butyl ester N-(pyridin-3-ylmethyl)-L-pyroglutamyl-L-tyrosinetert-butyl esterN-(pyridin-3-ylmethyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalanineN-(pyridin-3-ylmethyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalaninetert-butyl esterN-(pyridin-3-ylmethyl)-L-pyroglutamyl-L-4-[(4′-(pyridin-2-yl)piperazin-1′-yl)carbonyloxy]phenylalaninetert-butyl esterN-(pyridin-3-ylmethyl)-L-pyroglutamyl-L-4-[(4′-(pyridin-2-yl)piperazin-1′-yl)carbonyloxy]phenylalanineN-(4-benzyl-5-oxo-4-azatricyclo[4.2.1.0(3,7)]nonane-3-carbonyl)-L-tyrosinetert-butyl esterN-(4-benzyl-5-oxo-4-azatricyclo[4.2.1.0(3,7)]nonane-3-carbonyl)-L-4-(N,N-dimethylcarbamyloxy)phenylalaninetert-butyl esterN-(4-benzyl-5-oxo-4-azatricyclo[4.2.1.0(3,7)]nonane-3-carbonyl)-L-4-(N,N-dimethylcarbamyloxy)phenylalanineN-(4-fluorobenzyl)-L-pyroglutamyl-L-4-(N,N-dimethylcarbamyloxy)phenylalanineand pharmaceutically acceptable salts thereof, as well as any of theester compounds recited above wherein one ester is replaced with anotherester selected from the group consisting of methyl ester, ethyl ester,n-propyl ester, isopropyl ester, n-butyl ester, isobutyl ester,sec-butyl ester and tert-butyl ester.